Advantages of Digital thermometer:
Digital thermometer readings can be more readily combined with computer software.
Digital thermometer:
Compared to current clinical thermometers, it represents a step forward. There are now digital thermometers available that can measure temperature accurately without using mercury due to mercury's high toxicity and difficulties in disposing of it when a thermometer breaks.
Digital thermometers measure body temperature using heat sensors. They can be utilized to measure body temperatures in the mouth, rectum, or armpit.
Advantage: They are affordable, simple to read, lightweight, portable and need minimal upkeep, and provide precise readings.
Disadvantage: Eventually, the battery powering them runs out, and they are readily broken if dropped.
Liquid-based thermometer:
It is the most basic and widely used type of temperature measurement instrument.
Advantage: They are relatively less expensive. In contrast to electrical thermometers, they don't require a power source or batteries to charge.
Disadvantage: They are fragile, only suitable for manual reading applications, and cannot be automated or digitized. A glass thermometer's liquid components could be hazardous or harmful to your health since they could leak chemicals. Liquid-in-glass thermometer readings require excellent vision.
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Mia has a 32.0 g sample of Fe(OH)3 for the investigation purpose. How many
grams of oxygen be recovered from the sample?
O 3.6g
21.6 g
7.2 g
O 14.4 g
The amount of oxygen that can be recovered would be 14.37 grams
Percentage composition[tex]Fe(OH)_3[/tex] has 3 atoms of oxygen.
The percentage oxygen composition in the compound can be calculated as:
mass of oxygen content/total mass
The molar mass of the compound is 106.87 g/mol.
Percent oxygen = 3 x 16/106.87 x 100% = 44.91%
Thus, the amount of oxygen that can be recovered from 32.0 grams of Fe(OH)3 will be:
44.91/100 x 32 = 14.37 grams
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The value of Gfor a reaction conducted at 25C is 2.8 KJ/mol. The equilibrium for a reaction is _____ at this temperature.
The equilibrium constant of the reaction is 0.323.
Equilibrium constant:
It is expressed as the ratio of concentration of the products to the concentration of reactants. It is represented by K.
The relationship of K with G (Gibbs free energy) is expressed as:
G° = -RTlnK
Here R is the gas constant, T is the temperature.
Calculations:
Convert 25°C to K.
25°C = (25 + 273.15) K
= 298.15 K
Substitute the values in the above expression.
2.8 x 1000 J/mol = -8.314 J/mol.K x 298.15 K x ln(K)
lnK = 2800 J/mol/(-8.314 J/mol.K x 298.15 K)
lnK = -1.13
K = e^-1.13
= 0.323
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A sample of metal has a mass of 16.5916.59 g, and a volume of 5.815.81 mL. What is the density of this metal
Answer:
=> 2.8554 g/mL
Explanation:
To determine the formula to use in solving such a problem, you have to consider what you have been given.
We have;
mass (m) = 16.59 g
Volume (v) = 5.81 mL
From our question, we are to determine the density (rho) of the rock.
The formula:
[tex]p = \frac{m}{v}[/tex]
Substitute the values into the formula:
[tex]p = \frac{16.59 g}{5.81 mL} \\ = 2.8554 g/mL[/tex]
= 2.8554 g/mL
Therefore, the density (rho) of the rock is 2.8554 g/mL.
What is the freezing point, in °C, of
a 0.655 m solution of C4H10 in
benzene?
FP (benzene) = 5.5 °C
Kr(benzene) = 5.12°C/m
[?] °C
Give your answer to the thousandths place.
Freezing Point
Enter
The freezing point of the solution is - 2.15.
What is the freezing point?The freezing point is the point at which a liquid is changed to solid. We can use the formula;
ΔT = K m I
ΔT = temperature change
K = freezing constant of benzene
m = molality
i = Van't Hoff factor
Now;
ΔT = 5.12°C/m * 0.655 m * 1
ΔT = 3.35°C
ΔT = Freezing point of pure benzene - Freezing point of solution
Freezing point of solution = ΔT - Freezing point of pure benzene
= 3.35°C - 5.5 °C = - 2.15
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Answer:
2.143 degrees celsius
Explanation:
In molecules, c, h, o, and n atoms usually make __, __, __, and __ bonds respectively
Answer: " 4, 1, 2, 3."
_______________
" In molecules, C, H, O, and N atoms usually make _4_, _1_, _2_, and
_3_ bonds, respectively."
_______________
Note the following mnemonic device:
" H O N C " —> "Honc" if you love molecules!"
1 2 3 4 ;
{"hydrogen"} H → 1
{"oxygen"} O → 2
{"nitrogen"} N → 3
{"carbon"} C → 4
___
So: by using this mnemonic:
H O N C ;
1 2 3 4 ;
___
→ We can answer the question:
" C, H, O, N " → in sequence:
" 4, 1, 2, 3 " ;
{just use the corresponding numbers as per the mnemonic device.}.
The answer: " 4, 1, 2, 3 ".
Hope this is helpful to you! Best wishes!
Carbon fiber (CFRC) is generally stronger than steel, however, steel has a density that is about ____ compared to carbon fiber.
Carbon fiber Vs Steel:
Steel has a density that is about five times more when compared to carbon fiber.
What is Carbon fiber (CFRC):
Carbon is an element that occurs naturally, and carbon fiber is made of this element. Because of its crystalline structure, carbon fiber possesses excellent tensile strength and stiffness capabilities. It is used to create lightweight composite parts that have great strength by wrapping the fiber in a polymer matrix.
What is steel:
Steel has long been a preferred material due to its high elasticity, which is around 200 GPa. Its relative abundance and stiffness have made it a widely used manufacturing material. However, because of its weight and density of around 8 g/cm3, it can be exceedingly difficult on the machines it is intended to protect. This weighs nearly five times as much as carbon fiber materials which would offer an equivalent or higher level of stiffness.
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In a test of Charles' law, a gas inside a cylinder with a movable piston is heated to
315°C. The initial volume of gas in the cylinder is 0.30 L at 25°C. What will be the final
volume when the ttemperature is 315°C?
Answer:
3.78 L
Explanation:
The Charles' Law equation looks like this:
V₁ / T₁ = V₂ / T₂
In this equation, "V₁" and "T₁" represent the initial volume and temperature. "V₂" and "T₂" represent the final volume and temperature. You can find the final volume by plugging the give values into the equation and simplifying.
V₁ = 0.30 L V₂ = ? L
T₁ = 25 °C T₂ = 315 °C
V₁ / T₁ = V₂ / T₂ <----- Charles' Law equation
(0.30 L) / (25 °C) = V₂ / (315 °C) <------ Insert values
0.012 = V₂ / (315 °C) <----- Divide 25 from 0.30
3.78 = V₂ <----- Multiply both sides by 315
What is the symbol for temperature?
m
q
T
J
Answer:
T
Explanation:
m is mass
q is heat
J is energy
WILL GIVE BRAINLIEST
Question 9(Multiple Choice Worth 5 points)
(01.02 LC)
Which of the following is true about the weight of an object?
O It remains same for the object.
O It cannot be measured accurately.
O It is a force acting on the object.
O It is always less than the mass of the object.
PLS HELP
Answer:
It is a force acting on the object.
Explanation:
The answer option which is true about the weight of an object is: C. It is a force acting on the object.
Weight can be defined as the force acting on a physical body or an object as a result of gravity. Also, the weight of an object is measured in Newton.
Mathematically, the weight of an object is given by the formula;
Where;
m is the mass of the object.
g is the acceleration due to gravity.
In conclusion, the weight of an object is the force acting on an object due to gravity.
If 82.5 mol of an ideal gas occupies 10.5 l at 317 k, what is the pressure of the gas?
P=20707.7 atm
What is the molar form of the ideal gas law?The ideal gas law is a straightforward formula that describes the relationship between an ideal gas's pressure P, volume V, and temperature T. Unless there is a strong reason to treat gases differently, we normally treat gases as ideal because of how straightforward this relationship is:-
PV=nRT
where ;
P= Pressure=?
V= Volume= 10.5 L
n= no.of mol.= 82.5 mol
R=Ideal gas constant= 8.314 joule / mol kelvin
T=Temperature= 317 K
using Given value:-
P= nRT/ V
P=(82.5 x 8.314 x 317) / 10.5
P=20707.7 atm
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How many moles of sodium atoms is 5.43 x 10^24 atoms of sodium? *
Answer:
9.02 moles Na
Explanation:
To find the amount of moles, you need to multiply the given amount by Avogadro's Number. This number allows you to convert from atoms to moles of any substance.
Avogadro's Number:
6.022 x 10²³ atoms = 1 mole
5.43 x 10²⁴ atoms Na 1 mole
-------------------------------- x --------------------------------- = 9.02 moles Na
6.022 x 10²³ atoms
A nonpolar solvent has the highest solubility with a(n) _____ solute. A. polar B. nonpolar C. ionic D. electrically charged solute.
Answer:
nonpolar
Explanation:
A nonpolar solvent has the highest solubility with a nonpolar solute.
4 b + 3 o2 → 2 b2o3 if 8 moles of b and 4 moles of o2 are allowed to react, how many moles of b2o3 can be formed?
The number of moles of b2o3 that will be formed is determined as 4 moles.
Limiting reagent
The limiting reagent is the reactant that will be completely used up.
4 b + 3O₂ → 2b₂O₃
from the equation above;
4 b ------------> 2 b₂O₃
2b ------------> b₂O₃
2 : 1
3O₂ -------------> 2b₂O₃
3 : 2
b is the limiting reagent, thus, the amount of b2o3 to be formed is calculated as;
4 b ------------> 2 moles of b2o3
8 moles -------> ?
= (8 x 2)/4
= 4 moles
Thus, the number of moles of b2o3 that will be formed is determined as 4 moles.
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In a titration of 12.5 ML of 0.20m NaOH is used to neutralize 10.0 ML of HCL. Calculate the acid concentration
=> 0.25 M
The question is asking us to find the molarity/concentration of the acid (HCl).
We have been provided with;
12.50 mL of 0.20 M NaOH
10.0 mL of HCl
We know that molarity (M) of a solution is contained in 1 L or 1000 mL or 1000 cm³.
This means that;
0.20 M is contained in 1000 mL.
X mol is contained in 12.50 mL
[tex] x \: mol \: = \frac{12.50 \times 0.20}{1000} \\ = 0.0025 \: moles[/tex]
= 0.0025 moles
These 0.0025 moles is contained in 10 mL of HCl.
To find the molarity of the acid;
0.0025 moles is contained in 10 mL
x mol is contained in 1000 mL
[tex]x \: mol \: = \frac{0.0025 \times 1000}{10} \\ = 0.25 \: mol[/tex]
= 0.25 M
Therefore the Concentration of the acid (HCl) is 0.25 M
Which is the correct name for p2o5? phosphorus dioxide phosphorus pentoxide diphosphorus pentoxide diphosphorus hexaoxide
Correct option:
The correct name for [tex]P_{2}O_{5}[/tex] is diphosphorus pentoxide.
Why [tex]P_{2}O_{5}[/tex] is called diphosphorus pentoxide?
[tex]P_{2}O_{5}[/tex] is commonly known as diphosphorus pentoxide.
Phosphorus pentoxide has an intriguing property in that [tex]P_{2}O_{5}[/tex] is actually its empirical formula, whereas [tex]P_{4}O_{10}[/tex] is its actual molecular formula.
However, the name of the chemical was obtained from its empirical formula rather than from its molecular formula. The official name for this substance is diphosphorus pentoxide.
Oxygen-containing binary compounds have "oxide" as their "last name." Phosphorus is the "first name."
We list each atom's numbers below:
The di- and Penta- prefixes are used to indicate the presence of two and five oxygen atoms, respectively, in the molecule.
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Answer:
diphosphorus pentoxide
Explanation:
An aqueous solution contains
32.7% KCI (weight/weight %).
What is the mole fraction of KCI in
this aqueous solution?
Molar Mass
KCI: 74.55 g/mol
H₂O: 18.016 g/mol
Enter text here
Enter
Answer:
0.105 KCl
Explanation:
(Step 1)
If the solution is 32.7% KCl, we can assume that there are 32.7 grams KCl in the solution. This means that there would be 67.3 grams H₂O (100% - 32.7% = 67.3%) in the solution.
32.7% KCl = 32.7 g KCl
67.3% H₂O = 67.3 g H₂O
(Step 2)
Now, we need to convert both the solute (KCl) and the solvent (H₂O) into moles. This can be done by multiply the grams of each substance by their molar masses.
32.7 g KCl 1 mole
------------------ x -------------------- = 0.439 mole KCl
74.55 g
67.3 g H₂O 1 mole
------------------ x ----------------- = 3.74 moles H₂O
18.016 g
(Step 3)
Finally, we can calculate the mole fraction of KCl using the following equation. The final answer should have 3 sig figs to match the given value with the lowest amount of sig figs (32.7 g).
moles of solute
Mole Fraction = -----------------------------------------------------
moles of solute + moles of solvent
0.439 mole KCl
Mole Fraction = ------------------------------------------------------
0.439 mole KCl + 3.74 moles H₂O
Mole Fraction = 0.105 KCl
A balloon has a pressure of 3.1 atm at a volume of 155 ml. if the temperature is held constant, what is the volume (ml) if the pressure is increased to 10.5 atm?
Answer:
45.8 mL
Explanation:
If all variables are held constant, the new volume can be found using the Boyle's Law equation. The equation looks like this:
P₁V₁ = P₂V₂
In this equation, "P₁" and "V₁" represent the initial pressure and volume. "P₂" and "V₂" represent the final pressure and volume. You can find the new volume by plugging the given values into the equation and simplifying.
P₁ = 3.1 atm P₂ = 10.5 atm
V₁ = 155 mL V₂ = ? mL
P₁V₁ = P₂V₂ <----- Boyle's Law equation
(3.1 atm)(155 mL) = (10.5 atm)V₂ <----- Insert values
480.5 = (10.5 atm)V₂ <----- Multiply 3.1 and 155
45.8 = V₂ <----- Divide both sides by 10.5
what is the bond formed between N and Br
A) non-polar covalent
B) Polar Covalent
C) Ionic
Answer:
Bond between N and Br is non polar bond
Nitrogen being the element of group 15 , it required only 3 electrons to complete it's octace and BR, element of group 17 requires only one electron to complete it's octace both nitrogen and br share their electrons as for forming ionic bond it requires too much energy for nitrogen to remove 3 electrons also here, valency of br is only one. both are non metal so they formed covalent bond.The oxidation number of an element in a compound is equal to the charge the atoms would have if the compound was ___________. Select the correct answer below: ionic covalent molecular
The oxidation number of an element in a compound is equal to the charge of the atoms if the compound was an ionic compound.
What are types of compounds and how their oxidation number is calculated?The types of compounds are:
Ionic compoundsCovalent compounds and Molecular compoundsIonic compounds:
When a metal reacts with a non-metal an ionic compound is formed.The metal and ono-metals share electrons in between them and forms an anion and a cation respectively.The oxidation number of an ionic compound is equal to the charge of the ion.For a polyatomic ion, the sum of the oxidation numbers is equal to the charge of the ion.Covalent compound:
When non-metals reacts together a covalent compound is formed.They share electrons in between them by forming a covalent bond.The oxidation number of a covalent compound is the charge that results when the electrons are assigned to the more electronegative atom.Molecular compounds:
Molecular compounds are like the covalent compounds shares a covalent bond in between the atoms.The oxidation number of a molecule is given by gaining or losing of an electron by the atoms in it.Therefore, the oxidation number of an element in a compound is equal to the charge of the ion that would have if the compound was an ionic compound.
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A 0.261 g piece of solid magnesium reacts with gaseous oxygen from the atmosphere to form solid magnesium oxide. in the laboratory a student weighs the mass of the magnesium oxide collected from this reaction as 0.254 g. what is the percent yield ?
The percent yield of [tex]MgO[/tex] is 58.79%
According to the following balanced reaction, magnesium interacts with oxygen to generate magnesium oxide:
[tex]2Mg + O_2 \rightarrow 2MgO[/tex]
Given mass of solid magnesium = 0.261g
Molar mass of Mg = 24g/mol
Using formula , [tex]Number of moles =\dfrac {mass} {molar mass} = \dfrac {0.261g} {24g/mol} = 0.0108mole[/tex]
We could theoretically make 0.0108 moles of [tex]MgO[/tex] since the reaction yields an equimolar quantity of [tex]MgO[/tex]. It is clear from the above reaction that 2 moles of magnesium result in 2 moles of magnesium oxide.
Hence, mass of [tex]MgO[/tex] = Number of moles [tex]\times[/tex] Molar mass of MgO
mass of [tex]MgO[/tex] = [tex]0.0108mole \times 40g/mole = 0.432g[/tex]
Percent yield = [tex]\dfrac{Actual mass of MgO} {Theoretical mass of MgO} \times 100[/tex]
= [tex]\dfrac{0.254} {0.432} \times 100 = 58.79percentage[/tex]
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Compare the atomic sizes of sodium and magnesium. Explain.
Answer:
Sodium atom is larger than Magnesium atom.
Explanation:
Looking at the electronic configurations of Sodium and Magnesium:
[tex]_{11}Na: 1s^2 2s^2 p^6 3s^1\\\\_{12}Mg : 1s^2 2s^2 p^6 3s^2[/tex] ,
we can see that they both have their valence electrons in the 3rd shell.
But because Magnesium has a higher nuclear charge of +12 because of its 12 protons than that of Sodium's +11, the nucleus of Magnesium attracts its outer electrons more strongly than Sodium does. This makes the Magnesium atom smaller.
what might be a scientific question
Answer:
Example of a scientific question:
Does the angle of a ramp change the distance a toy car will travel?
Explanation:
Using the name of the ionic compound, select the appropriate chemical formula. Use the periodic table
that has been provided. Click here to access the common polyatomic ion sheet
Ammonium Phosphate
The compound Ammonium Phosphate is (NH4)3PO4 while that of sodium acetate is NaC2H3O2.
What is an ionic compound?An ionic compound is compound that is composed of ions. We know that a poly atomic ion is an ion that contains more than one atom.
Looking at the options that have been provided, we know that the correct formula for the compound Ammonium Phosphate is (NH4)3PO4 while that of sodium acetate is NaC2H3O2.
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If a radioactive decay produced 1.26 × 1012 J of energy, how much mass was lost in the reaction?
The mass lost in the process is 1.4 * 10^-5Kg.
What is the Einstein equation?The Einstein equation is able to relate the mass lost to the energy that is evolved in a nuclear process.
Given that;
E = Δmc^2
Δm = E/c^2
Δm = 1.26 × 10^12 J/( 3 * 10^8)^2
Δm = 1.4 * 10^-5Kg
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Which is the correct mole ratio of
K PO to KNO in the chemical
reaction
Mg(NO₂)₂ (aq) + K,PO (aq) -->
Mg (PO )₂(aq) + KNO₂(aq)?
The correct mole ratio of K₃PO₃ and KNO₂ in the chemical reaction is 1 : 3
Balanced equation3Mg(NO₂)₂ (aq) + 2K₃PO₃ (aq) -> Mg₃(PO₃)₂(aq) + 6KNO₂(aq)
from the balance equation,
The number of mole of K₃PO₃ = 2 molesThe number of mole of KNO₂ = 6 molesHow to determine the mole ratio of K₃PO₃ and KNO₂Number of mole of K₃PO₃ = 2 molesNumber of mole of KNO₂ = 6 molesMole ratio of K₃PO₃ and KNO₂ =?Mole ratio = mole of K₃PO₃ / mole of KNO₂
Mole ratio of K₃PO₃ and KNO₂ = 2 / 6
Mole ratio of K₃PO₃ and KNO₂ = 1 : 3
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Ascorbic acid (Vitamin C) is a diprotic acid, H₂C6H6O6. What is the pH of a 0.10 M
solution? What will be the concentration of C6H6O62-? Ka1 = 7.9 x 105 and Ka2 = 1.6 x 10-12
The pH of the solution is 1.52 and the concentration of C6H6O62- is 2.2 * 10^-7 M.
What is the concentration of C6H6O62-?We know that;
H₂C6H6O6 ⇔HC6H6O6^-(aq) + H^+(aq) ----- (1)
Ka1 = 7.9 x 10^-5
Again;
HC6H6O6^-(aq) ⇔ C6H6O6^2-(aq) + H^+(aq) ------- (2)
Ka2 = 1.6 x 10^-12
Given that Ka2 <<<< Ka1 we have to apply equation 1 to obtain H^+ hence;
Ka1 = [HC6H6O6^-] [H^+]/[H₂C6H6O6]
Let [HC6H6O6^-] = [H^+] =x
7.9 x 10^5 =x^2/0.1 - x
But x <<< 0.1 thus;
7.9 x 10^5 =x^2/0.1
x = √7.9 x 10^-5 * 0.1
x = 0.03 M
pH = -log(0.03 M)
pH = 1.52
To obtain C6H6O6^2-;
Ka2 = [ C6H6O6^2-] [ H^+]/[HC6H6O6^-]
Also;
[ C6H6O6^2-] = [ H^+]= x
Now;
1.6 x 10^-12 = x^2/0.03 -x
But x<<<0.3
Hence;
1.6 x 10^-12 = x^2/0.03
x = √1.6 x 10^-12 * 0.03
x = 2.2 * 10^-7 M
The concentration of C6H6O6^2- is 2.2 * 10^-7 M.
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Which of the following statements is true?
A. A high atom economy means that most of the starting materials end up as waste products.
B. The actual yield of a reaction is the amount of product you expected to make.
OC. A reaction with a high percentage yield is an efficient reaction.
D. The percentage yield of a reaction can be over 100%.
Answer:
B. The actual yield of a reaction is the amount of product you expected to make.
Explanation:
The actual yield of a reaction is the quantity of a product that is obtained from a chemical reaction. Therefore part B is the right solution to our question since it is true that actual yield of a reaction is the amount of product you expected to make.
Q1. What are decomposition reactions? Explain with the help of a balanced chemical equation. (2 marks)
Q2. Draw the structure of a nephron and label the following on it- Glomerulus, Bowman’s capsule, Renal artery and Collecting duct. (2 marks)
Q3. What happens when zinc metal reacts with sulphuric acid? Write the chemical equation involved in this reaction. (2 marks)
Q4. Draw ray diagrams showing the image formation by a convex lens when an object is placed (2 marks)
(a) between optical centre and focus of the lens
(b) between focus and twice the focal length of the lens
Q5. Sunita and her mother had an appointment with an optician. Optician prescribed corrective lenses to Sunita having a power equal to + 5.0 D. The lens prescribed to
her mother has power equal to – 2.5 D. (3 marks)
(a) What is the focal length of the lens prescribed to Sunita?
(b) Which type of spherical lens is prescribed to Sunita’s mother?
(c) What is the power of the combination of the two lenses (if placed in contact), prescribed to Sunita and her mother?
Q6. Give the reason for the following: (3 marks)
(a) The taste and smell of chips change when the packet is left open for a few days.
(b) Magnesium ribbon is cleaned before burning in air.
(c) Iron articles get coated with reddish brown powder when left for sometime.
Q7. (a) Why do arteries have thick and elastic walls while veins have thin walls? (2 marks)
(b) What is the role of valves in the heart? (1 mark)
Decomposition reaction represents the breakdown of single compound into more products.
What are decomposition reactions?A decomposition reaction is a type of reaction in which one reactant breaks down into two or more products. This can be represented by the general equation: H2O2 → 2H + 2O. In this example the breakdown of hydrogen peroxide occurs and water and oxygen are formed.
What happens when zinc metal reacts with sulphuric acid?Zinc reacts with dilute sulphuric acid to form zinc sulphate and hydrogen This hydrogen goes up into the atmosphere whereas the zinc sulphate remains.
Why should a magnesium ribbon be cleaned before burning in air?Magnesium ribbon should be cleaned before burning in air because Magnesium metal combines with oxygen to form Magnesium Oxide (MgO) layer, which is a very stable molecule.
Why arteries have thick, elastic walls, while veins have thin walls?Arteries have thick, elastic walls, while veins have thin walls because arteries are under more pressure, as compared to veins that are under less pressure. Arteries are big in size whereas veins are small.
What is the role of valves in the heart?The role of valves in the heart is that these valves prevent the backward flow of blood.
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How many grams of NH3 form when 22g H2 react completely?
The Answer to the question is 124.66 grams approximately.
It is given that H₂ will react completely
Molar mass of H₂ = 2 × 1 = 2 gm/mol
Given mass of H₂ = 22 gm
Moles of H₂ reacting = given mass of H₂ / molar mass of H₂
Moles of H₂ reacting = 22 / 2 moles = 11 moles
So, 11 moles of H₂ are taking part in reaction.
The Balanced chemical reaction is as follows as:
N₂ + 3 H₂ → 2 NH₃
It is clear from the reaction that 3 moles of H₂ are making 2 mole of NH₃
3 moles of H₂ → 2 mole of NH₃
1 moles of H₂ → 2/3 mole of NH₃
11 moles of H₂ → (2/3)×11 mole of NH₃
11 moles of H₂ → 22/3 mole of NH₃
So, 11 moles of H₂ will make 22/3 mole of NH₃
22/3 mole NH₃ = mass formed NH₃ / molar mass of NH₃
mass formed NH₃ = 22/3 × molar mass of NH₃
mass formed NH₃ = 22/3 × 17
mass formed NH₃ = 22/3 × 17
mass formed NH₃ = 124.66 grams (approximately)
124.66 grams of NH₃ will be formed.
So, approximately 124.66 grams of NH₃ is formed from 22 grams of H₂.
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Which statement best describes the science of chemistry?
A. Chemistry is mainly the study of energy and forces in matter in the
universe.
B. Chemistry is mainly the study of forces in matter.
C. Chemistry is mainly the study of the composition of and changes
in matter.
D. Chemistry is mainly the study of matter in living things.
Answer:
Explanation:Matter is anything that has weight and occupies space