Answer:
B. Move the beaker to the center of the hot plate
Explanation:
The erratic and unstable stirring might be caused by the beaker not being properly balanced on the hot place, there by distorting the the center of gravity of the stirring motion.
In properly positioning the stirrer to the hot plate, the magnetic rod is positioned to the center of the fluid, allowing for a more fluid and even effective stirring.
I hope this was helpful.
An element has 4 protons, 5 neutrons, and 4 electrons. Choose the correct answer. *
Answer:
4
Explanation:
[tex]\int\limits^a_b {x} \, dwetjernjtnx[/tex]
Liquid hexane CH3CH24CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 5.2 g of hexane is mixed with 33.0 g of oxygen. Calculate the minimum mass of hexane that could be left over by the chemical reaction. Be sure your answer has the correct number of significant digits.
Answer:
The leftover is 15 g of oxygen rather than liquid hexane as the fuel limits the reaction.
Explanation:
Hello!
In this case, since the described combustion reaction is:
[tex]C_6H_{14}(l)+\frac{19}{2} O_2(g)\rightarrow 6CO_2(g)+7H_2O(g)[/tex]
Thus, since 5.2 g of hexane (86.2 g/mol) is reacted with 33.0 g of oxygen (32.0 g/mol) we can compute the mass of hexane that was actually consumed via stoichiometry with oxygen (1:19/2 mole ratio):
[tex]m_{C_6H_{14}}^{consumed \ by\ O_2}=33.0gO_2*\frac{1molO_2}{32.0gO_2}*\frac{1molC_6H_{14}}{\frac{19}{2}gO_2 } *\frac{86.2gC_6H_{14}}{1molC_6H_{14}} \\\\m_{C_6H_{14}}^{consumed \ by\ O_2}=9.36gC_6H_{14}[/tex]
It is proved then than the hexane won't have any leftover but oxygen does, as shown below:
[tex]m_{O_2}^{consumed \ by\ C_6H_{14}}=5.2gC_6H_{14}*\frac{1molC_6H_{14}}{86.2gC_6H_{14}} *\frac{\frac{19}{2}molO_2 }{1molC_6H_{14}} *\frac{32.0gO_2}{1molO_2} \\\\m_{O_2}^{consumed \ by\ C_6H_{14}}=18g[/tex]
It means the leftover of oxygen is:
[tex]m_{O_2}^{leftover}=33g-18g\\\\m_{O_2}^{leftover}=15g[/tex]
Regards!
If 49.0 g of O2 is mixed with 49.0 g of H2 and the mixture is ignited, what is the maximum mass of water that may be produced?
Answer:
[tex]55.2gH_2O[/tex]
Explanation:
Hello!
In this case, since the reaction between hydrogen and oxygen to produce water is:
[tex]2H_2+O_2\rightarrow 2H_2O[/tex]
When equal masses of each reactant go in contact to carry out the reaction, we can identify the maximum mass of yielded water as the fewest mass yielded by each reactant, just as shown below:
[tex]m_{water}^{by\ H_2}=49.0gH_2*\frac{1molH_2}{2.02gH_2}*\frac{2molH_2O}{2molH_2}*\frac{18.02gH_2O}{1molH_2O} =170gH_2O\\\\m_{water}^{by\ O_2}=49.0gO_2*\frac{1molO_2}{32.0gO_2}*\frac{2molH_2O}{1molO_2}*\frac{18.02gH_2O}{1molH_2O} =55.2gH_2O[/tex]
Thus, since hydrogen yields more water than real, we limit the maximum mass of water to those 55.2 g yielded by oxygen as hydrogen would be in excess.
Best regards!
Calculate the amount of heat (in J) needed to raise the temperature of 3.50 g of water from 22.4oC to 98.8oC.
Answer:
76.4oC or 169.52oF
Explanation:
That's the amount of heat needed
The heat capacity is the heat amount lost or gained by the object in a thermodynamic system. The heat needed to raise the temperature of the water is 1117.7 Joules.
What is heat capacity?Heat capacity (q) is the heat an object loses or gains to alter the temperature of the thermodynamic system by a difference of a degree Celsius. The heat capacity is given by the mass, specific heat capacity, and temperature change.
Given,
Mass of water (m) = 3.50 gm
Specific heat (c) = 4.18 J/ g°C
The temperature change (∆T) = T₂ - T₁
= 98.8 °C - 22.4 °C
= 76.4 °C
The heat capacity is given as,
q = mc∆T
Substituting values above:
q = 3.50 gm × 4.18 J/ g °C × 76.4 °C
q = 1117.7 J
Therefore, 3.50 g of water has a heat capacity of 1117.7 Joules.
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A river and all of its tributaries make up a(n) _________.
Answer:
A river and its tributaries make up a watershed (aka river system or drainage basin)
Pls mark me as brainliest
Answer:
river system
Explanation:
a river and all its tributaries make up a river system
Name something that has zero thermal energy.
Answer:
When all molecules in a system stop moving completely, there is zero thermal energy
Explanation:
It is impossible to reach though
PLZ HELP PLZ
NO WRONG ANSWERS
Answer:
it is C
Explanation:
because Potassium iodide (KI) is an ionic compound which is made of the following ions: K+I−
A gas has a volume of 6.00 liters at a temperature of 27° C and a pressure of 1,00 atm. What is the volume of the gas, in liters, at a temperature of 327°C and a
pressure of 3.00 atm?
We are given:
P1 = 1 atm P2 = 3 atm
T1 = 300 K T2 = 600 K
V1 = 6 L V2 = v L
Finding the final Volume:
From the ideal gas equation:
PV = nRT
since in the given scenario, the universal gas constant (R) and number of moles(n) are constant
So, for both the cases, the value of n*R will be a constant k
Hence, we can write that:
PV / T = k [where k is a constant]
Since the constant 'k' is the same for both the cases, we can write that:
P1V1 / T1 = P2V2 / T2
replacing the variables
1 * 6 / 300 = 3 * v / 600
1/50 = v / 200
v = 200/50
v = 4 L
Therefore, the volume of the gas at 600K and 3 atm will have a volume of 4 L
Is iron man made or natural
Answer:
Iron is natural. Paper is man-made
Explanation:
Answer:
iron
Explanation:
a solution is dilute when?
A. it has a lot of solute
B. has little solvent
C. it has a lot of solvent
D. has maximum solute
an ionic bond is a force of _____between anions and ______when combined make _____compounds that are electrically_____
According to the following reaction, how many moles of hydrobromic acid are necessary to form 0.274 moles bromine?
hydrobromic acid (aq) —>hydrogen (g) + bromine (1)
moles hydrobromic acid
Answer:
0.548 moles of HBr are required
Explanation:
Given data:
Number of moles of hydrobromic acid = ?
Moles of bromine formed = 0.274 mol
Solution:
Chemical equation:
2HBr → H₂ + Br₂
Now we will compare the moles of HBr with Br₂.
Br₂ : HBr
1 : 2
0.274 : 2×0.274=0.548
Thus, 0.548 moles of HBr are required.
chlorine monobromide ionic or molecular
which type of energy change causes a
leaf to grow
Electromagnetic energy
Explanation:
Growth is one of the characteristics of living things. It refers to the increase of an organism. A leaf is part of a plant, which is a photosynthetic organism i.e. an organism capable of producing its own food using energy from sunlight. Light energy is a part of the ELECTROMAGNETIC ENERGY.
This light energy is used to synthesize glucose (food) via photosynthesis. The glucose, which stores chemical energy in its bond is then broken down to yield ATP used for growth. Hence, the transformation of electromagnetic energy to light energy is how a leaf grow.
Weathering is the process that takes place as rocks, and other parts of the geosphere, are??
A solution containing molecular nonpolar molecules will conduct electricity
True or False?
Answer:
true
Explanation:
How do you think energy flows in and out of the earth's atmosphere ?
Look at the picture below. Name the isotope.
Answer:
carbon-13
Explanation:
Consider a monoprotic weak acid ( HAHA ) that is titrated with a strong base. What is the relationship between the strength of the weak acid and the pH of the solution at the equivalence point?A. There is no relationship between the strength of the acid and the pH at the equivalence point. B. The pH at the equivalence point is always 7 in an acid base titration. C. The weaker the acid, the higher the pH at the equivalence point. D. The stronger the acid, the higher the pH at the equivalence point.
Answer:
C. The weaker the acid, the higher the pH at the equivalence point.
Explanation:
In a titration, a solution which concentration is known is added gradually to another solution of unknown concentration, until the chemical reaction between the two solutions is complete.
The pH in the equivalence point is equal to 7.00 only if both the acid and base are strong. When one or both reactants are weak, the pH in the equivalence point is not equal to 7.00.
In the equivalence point, the amount of strong base (like NaOH) added is just enough to react stoichiometrically with the weak acid. The resulting solution "only" contains the conjugated base A⁻. A solution of Na⁺A⁻ is the solution of a weak base:
A⁻ + H₂O ⇄ HA + OH⁻ Kb=Kw/Ka
In the equivalence point of the titration of a weak base with a strong base, the pH is higher than 7.00 because at this point the acid is transformed into its conjugate base.
At what temperature does water freeze in Celsius
Answer:
32°c
Explanation:
Because in F it would be 0°f
I need help, due in 30 mins
Answer:
1.Reaction rate is how fast a chemical reaction proceeds.
2.Nature of the reaction, Pressure factor
, Solvent, Catalyst and inhibitors.
3.Physical change is a temporary change. A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc.
4. One example of the effect of temperature is the use of lightsticks or glowsticks.
5.When the particle size of a fixed mass of a solid reactant becomes smaller, the total exposed surface area becomes larger, the rate of reaction increases. an example could be ice and water when the atoms are stuck together a solid but all over the place as a liquid.
6. Sometimes a reaction depends on catalysts to do their job. In that case, changing the concentration of the catalyst can speed up or slow down the reaction. For example, enzymes speed up biological reactions, and their concentration affects the rate of reaction.
7.A catalyst is a chemical substance that affects the rate of a chemical reaction by altering the activation energy required for the reaction to proceed. For example, a catalyst could cause a reaction between reactants to happen at a faster rate or at a lower temperature than would be possible without the catalyst.
Explanation:
I hope this helps have a great day! :)
a sample of lead had a mass of 150 g. The molar mass of lead is 207.19 g. How many moles of lead does the sample contain?
Answer:
Explanation:
no of moles=given mass/molar mass
no of moles=150 g/207.19
no of moles=0.72
We will use dimensional analysis to answer this question.
[tex]150 g * \frac{1 g}{207.19 mol} = 0.724 mol[/tex]
The answer is 0.724 mol.
the difference in energy between the n=1 and n=2 energy levels in a hydrogen atom is 1.64x10^-18 J. what happens when an electron in a hydrogen atom transitions from n=2 to n=1?
Answer:
It emits 1.64 x 10⁻¹⁸J of energy
Explanation:
The n = 1 is a lower quantum level compared to n = 2.
When a hydrogen atom moves from a higher level to a lower one, it simply emits the energy difference between the two levels.
If a hydrogen atom moves from a lower energy level to a higher one such as from 1 to 2, they absorb the energy difference to attain the new excited state. So, for an electron in the hydrogen atom to move from a higher energy level to a lower one, it must emit 1.64 x 10⁻¹⁸J of energy.The sample of 15.0 g of KCl is dissolved into a solution with a total volume of 250.0 mL. What is the molarity of KCl in the solution?
Answer:
0.805 M.
Explanation:
Hello!
In this case, since the molarity of a solution is computing by dividing the moles of solute over the volume of solution in liters (M=n/V), for 15.0 g of potassium chloride (74.55 g/mol) we compute the corresponding moles:
[tex]n=15.0gKCl*\frac{1molKCl}{74.55gKCl}=0.201molKCl[/tex]
Next, since the volume is 0.2500 in liters, the molarity turns out:
[tex]M=\frac{0.201mol}{0.2500L} \\\\M=0.805M[/tex]
Best regards!
how could you tell what element it is if only a model was present?
How does evidence of chemical
reactions indicate that new substances
with different properties are formed?
Answer:
Changes in Properties Changes in properties result when new substances form. For instance, gas production, formation of a precipitate, and a color change are all possible evidence that a chemical reaction has taken place. ... Change in Color A color change can signal that a new substance has formed.
Explanation:
The chemical reaction indicate the formation of new substance by change in nature of original compound and shows chemical changes in the reaction.
What is chemical reaction?Chemical reaction is defined as process in which two or more molecules collide with the proper orientation and enough force to produce a new product.
It is also defined as a procedure in which one or more compounds, known as reactants, are changed into one or more distinct substances, known as products.
There are mainly seven types of reaction.
Synthesis reactionDecomposition reactionDisplacement reactionDouble displacement reactionCombustion reactionRedox reactionAcid-Base reactionThus, the chemical reaction indicate the formation of new substance by change in nature of original compound and shows chemical changes in the reaction.
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Please i really need help it's due today
Answer:
there is your answer hope it helped :3
Once a rate law is determined from trials with concentration and rate data, what is the minimum number of additional trials that will have to be done to gather sufficient initial rates data to be able to find the rate constant for the reaction? a. 0b. 1c. 2d. 3
Answer:
A is probably ur answer
Explanation:
but if I'm wrong My bad and at least I tried
an ionic bond forms when atoms blank electrons
Answer:
An ionic bond forms when atoms transfer electrons.
Explanation:
Ionic bonds are formed when atoms transfer electrons. (In contrast, covalent bonds are formed when atoms share electrons.)
There's a distinction between the two: when two atoms react to form an ionic bond, one atom would completely lose one electron, while the other would completely gain that electron. The atom that loses the electron becomes a positively-charged ion called a cation, whereas the atom that gains the electron becomes a negatively-charged ion called an anion.
For example, consider the reaction between a sodium [tex]\rm Na[/tex] atom and a chlorine [tex]\rm Cl[/tex] atom: [tex]\rm Na + Cl \to NaCl[/tex].
When the sodium atom and the chlorine atom encounter, the sodium atom would lose one electron to form a positively-charged sodium ion, [tex]\rm Na^{+}[/tex]. The chlorine atom would gain that electron to form a negatively-charged chlorine ion [tex]\rm Cl^{-}[/tex].
These two ions will readily attract each other because of the opposite electrostatic charges on them. This electrostatic attraction (between two ions of opposite charges) is an ionic bond.
Overall, it would appear as if the sodium [tex]\rm Na[/tex] atom transferred an electron to the chlorine [tex]\rm Cl[/tex] atom to form an ionic bond.
In contrast, when two atoms react to form a covalent bond, they share electrons without giving any away completely. Therefore, it is possible to break certain covalent bonds apart (using a beam of laser, for example) and obtain neutral atoms.
On the other hand, when an ionic bond was broken, the result would be two charged ions- not necessarily two neutral atoms. The electron transfer could not be reversed by simply breaking the bond.
For example, when table salt [tex]\rm NaCl[/tex] is melted (at a very high temperature,) the ionic bond between the sodium ions and chloride ions would (mostly) be broken. However, doing so would only generate a mixture of [tex]\rm Na^{+}[/tex] and [tex]\rm Cl^{-}[/tex] ions- not sodium and chlorine atoms.
Answer:yea it’s transfer
Explanation:
Help ASAP
Please and thank you
Answer: C
Explanation: Everything else is true.