156 grams of calcium fluoride, CaF2, is dissolved in 2000 mL of solution. Determine the molarity (M).
Answer:
1 M
Explanation:
We'll begin by calculating the number of mole of in 156 g of CaF₂. This can be obtained as follow:
Mass of CaF₂ = 156 g
Molar mass of CaF₂ = 40 + (19×2)
= 40 + 38
= 78 g/mol
Mole of CaF₂ =?
Mole = mass /molar mass
Mole of CaF₂ = 156 / 78
Mole of CaF₂ = 2 moles
Next, we shall convert 2000 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
2000 mL = 2000 mL × 1 L / 1000 mL
2000 mL = 2 L
Finally, we shall determine the molarity of the solution. This can be obtained as follow:
Mole of CaF₂ = 2 moles
Volume = 2 L
Molarity =?
Molarity = mole / Volume
Molarity = 2 / 2
Molarity = 1 M
Thus, the molarity of the solution is 1 M
In the lab, you are asked to plan an investigation that shows how the structure of substances can explain the strength of the electrical forces between
particles. To show this, you decide to determine how much tinfoil will melt when the heat of different objects touches it. One of the objects you test
releases 5.7 kJ of heat. How much of the tinfoil will melt?
AHjus=7.029 kJ/mol
O
A. 16.99
B. 20.89
C. 84.39
D. 96.39
How many different chlorinated products
are based in the following reaction.
CH3CH2CH2CH3 + Cl2 heat
Answer: if I’m not mistaken it would be 8
Explanation:
Answer:
2
Explanation:
:)
Students are asked to design an experiment with cookies to demonstrate their understanding of the scientific method. One group has decided to determine the amount of time it will take for a cookie to "dissolve" in a glass of milk.
Which variable would most likely NOT affect the time it takes for the cookie to dissolve?
a) the size of the cup of milk
b) the type of cookie
c) the number of students in the group
d) the temperature of the milk
e) the type of milk
I'm gonna guess E on this one, but I think you should choose either E or A
Why is it dangerous to stand under tall trees and building during thunder?
Somebody please answer
60 L of a 180 mol MgCl2 solution is created. What is the molarity of MgCl2 are in this solution?
Explanation:
Molarity = (# of moles)/(# of liters)
= 180 mol MgCl2/60 L
= 3.0M MgCl2
Choose the molecule or compound that exhibits dipole-dipole forces as its strongest intermolecular force.
BCl3CBr4SO2H2H2O
Answer:
SO2
Explanation:
Dipole-Dipole exist between parmanent dipoles in a molecule. THis means that molecule must have a parmanent dipole moment in it.
Example - HCl
Hydrogen bonding is an attraction between lone pair of an electronegative element and H atom of same or different molecule. H must be covalantly attached to either F, N or O.
Example - H2O
Among the molecules given in the list only SO2 and H2O exihibits parmanent moment. As BCl3 , CBr4 and H2 are symmetric compounds.
Since, SO2 cannot exihibit H- bonding only dipole-dipole forces as its strongest intermolecular force.
2. All of the following statements are true regarding wood versus metal except: a) Wood has better electrical insulation which decreases with moisture content b) Wood structures dampen vibrations much better than metal, due to internal friction within the materials c) Under sustained loads wood stops to deform d) Wood has much better R value than metals
Answer:
All of the following statements are true regarding wood versus metal except:
c) Under sustained loads wood stops to deform
Explanation:
Wood is known to deform under stress. It undergoes warping, thereby, losing its original straight shape when its moisture unevenly dries up. Even concrete deforms under long-time loads. Similarly, wood, under sustained loads, experiences faster deformation than it ordinarily warps. To prevent further wood deformation, it must be treated, and its moisture dried up evenly.
What is the pH of a 0.025 M HCl solution?
12.4
1.6
2.5
05
Answer: pH is 1.6
Explanation: Explanation: HCl is strong acid and it protolyzes totally:
HCl + H2O ⇒ H3O+ + Cl-
Concentrations are same: [H3O+] = c(HCl)
pH = - log[H3O+] = - log(0.025) = 1.60
One of the governing laws of the universe is the thermodynamic law of entropy. Which choice best describes entropy?
A. Particles and energy in a system become more and more disordered.
B. Energy is consumed in a chemical reaction.
C. Heat is evenly distributed throughout the universe.
D. More bonds are broken in a chemical reaction than bonds are formed.
A.
Particles and energy in a system become more and more disordered.
What're the differences between oxidation and reduction
Answer:
Oxidation:Oxidation is the loss of electron or Hydrogen atoms or gain of Oxygen atomsRemoval or loss of electronsA ⟶ A⁺ + e⁻
Removal of HydrogenAH + B ⟶ A + BH
Addition of OxygenA + BO ⟶ AO + B
All the above reactions release energy Reduction:Reduction is the gain of electron or Hydrogen atoms or loss of Oxygen atomsAddition or gain of electronsA + e⁻ ⟶ A⁻
Addition of HydrogenA + BH ⟶ AH + B
Removal of OxygenAO + B ⟶ A + BO
All the above reactions stores energy-TheUnknownScientist
Which
gas is exchanged in the air sac of
longs? -
oxygen and nitrogen
oxygen and carbondioxide
O nitrogen and coarbondioxide
oxygen and hydrogen
O
Other:
Answer:
oxygen and carbon dioxide.
hope this helps you
Consider the energy diagram below.
AY
B
Free Energy
Reaction Progression
Which line indicates a higher reaction rate?
A because it has a lower activation energy.
B because it has a lower activation energy.
Answer:
B because it has a lower activation energy.
Explanation:
Just took the test
[H] = 1.00 x 10^-7 M
a. Acidic
b. Basic
c. Neutral
A chemistry student weighs out 0.021 kg of an unknown solid compound X and adds it to 650. mL of distilled water at 30. 0C. After 10 minutes of stirring, all of the X has dissolved. Just to be sure, the student adds a further 11. mg of X to the solution, and it, too, dissolves. Using only the information above, can you calculate the solubility of X in water at 30. 0C?
Answer:
"No" I can't calculate the solubility of X.
Explanation:
Beyond certain temperatures or heat levels, a solvent's soluble has been determined by many as the proportion of something like the solution necessary for saturating the solvents' measured amount at around that atmospheric pressure.This same solution isn't absorbed throughout this situation. It is not saturated however since the addition of 11 g of something like the mixture towards the solution completely dissolved without separating a solution.This is why the preceding solution would be the proper one.
What is the volume of 1.00 kg of mercury?
Answer:0.074 L
Explanation:
During a combustion reaction, 9.00 grams of oxygen reacted with 3.00 grams of CH4.
What is the amount of the leftover reactant?
0.74 grams of methane
0.89 grams of methane
1.22 grams of oxygen
1.45 grams of oxygen
Answer:d
Explanation:
A mixture of fuel and is injected into a cylinder fitted with a piston. The initial volume is 0.37 L. After the mixture is ignited, gaseous products are formed and 1885 J of energy is released by the reaction. 311 J of the released energy is lost as heat to the surroundings. To what volume would the gases expand against a constant pressure of 1.036 atm, if the remainig energy is converted to work to push the
Answer:
The gases will expand to a volume of 2.37 L
Explanation:
Gases are able to do work when they expand or compress against an external constant pressure.
This work done by gases when they expand or compress against a constant external pressure is known as pressure-volume work or PV work.
The formula for calculating the work done by gases when they compress or expand against a constant pressure is given as W = PΔV
Where ΔV is change in volume given as V2 - V1
Where V2 is final volume, V1 is initial volume
By convention, W can either be negative or positive. When work is done by the system (ΔV > 0), W is negative and when work is done on the system (ΔV < 0), W is positive.
In the gas mixture above, W = PΔV
Remaining energy, W = (1885 - 311) J = 1574 J
P = 1.036 atm = 1.036 × 760 mmHg = 787.36 mmHg
ΔV = V2 - V1
ΔV = V2 - 0.37
1574 = 1.036 (V2 - 0.37)
V2 - 0.37 = 1574/787.36
V2 - 0.37 = 1.999 L
V2 = 1.999 + 0.37
V2 = 2.369 L
Therefore, the gases will expand to a volume of 2.37 L
Metal plating is done by passing current through a metal solution. For example, an item can become gold plated by attaching the item to a power source and submerging it into a Au3 solution. The item itself serves as the cathode, at which the Au3 ions are reduced to Au(s). A piece of solid gold is used as the a node and is also connected to the power source, thus completing the circuit.
Required:
What mass of gold is produced when 15.0A of current are passed through a gold solution for 15.0min ?
Answer:
9.18g
Explanation:
Step 1: Write the reduction half-reaction
Au³⁺(aq) + 3 e⁻ ⇒ Au(s)
Step 2: Calculate the mass of gold is produced when 15.0A of current are passed through a gold solution for 15.0min
We will use the following relationships:
1 min = 60 s1 A = 1 C/s1 mole of electrons has a charge of 96486 C (Faraday's constant).1 mole of Au is produced when 3 moles of electrons circulate.The molar mass of Au is 196.97 g/mol.The mass of gold produced is:
[tex]15.0 min \times \frac{60s}{1 min} \times \frac{15.0C}{1s} \times \frac{1 mol e^{-} }{96486C} \times \frac{1molAu}{3 mol e^{-} } \times \frac{196.97gAu}{1molAu} = 9.18gAu[/tex]
Calculate the pressure of 2.50 Liters of a gas at 25.0oC if it has a volume of 4.50 Liters at
STP.
Answer:
P_2 =0.51 atm
Explanation:
Given that:
Volume (V1) = 2.50 L
Temperature (T1) = 298 K
Volume (V2) = 4.50 L
at standard temperature and pressure;
Pressure (P1) = 1 atm
Temperature (T2) = 273 K
Pressure P2 = ??
Using combined gas law:
[tex]\dfrac{P_1V_1}{T_1} = \dfrac{P_2V_2}{T_2} \\ \\ \dfrac{1 *2.5}{298} = \dfrac{P_2*4.5}{273}[/tex]
[tex]0.008389261745 \times 273 = 4.5P_2[/tex]
[tex]P_2 =\dfrac{0.008389261745 \times 273 }{4.5}[/tex]
[tex]P_2 =0.51 \ atm[/tex]
Can someone give me an example of balancing equations with a solution that is simple?
Explanation:
[tex]H _{2}O _{2(aq)} →H _{2}O _{(l)} + O _{2}(g) \\ solution : 2 \: and\: 2[/tex]
How much ammonia would it take to neutralize 5ml of apple cider and 5ml of white vinegar if the ammonia had a molarity of 0.25?
Answer:
[tex]m_{NH_3}=0.0213gNH_3[/tex]
Explanation:
Hello there!
In this case, since it is known that the reaction between ammonia and acetic acid is:
[tex]CH_3COOH+NH_3\rightarrow CH_3COONH_4[/tex]
It is possible for us to realize that the mole ratio of acetic acid (vinegar) to ammonia is 1:1, that is why we can relate the concentrations as follows:
[tex]M_{acid}V_{acid}=M_{base}V_{base}\\\\[/tex]
In such a way, by knowing that the volume of these two are the same, we infer that their concentrations is also de same; and therefore, the mass of ammonia is calculated as:
[tex]m_{NH_3}=0.005L*0.25\frac{molNH_3}{L}*\frac{17.04gNH_3}{1molNH_3}\\\\m_{NH_3}=0.0213gNH_3[/tex]
Regards!
Which laws protect citizens against human trafficking
Answer:
It depends on the country you are coming from. For example, the human trafficking laws in the US are different from UK. If you need an essay on this contact me on (irenedavid at g mail dot com)
Explanation:
A or B or C or D plzz answer fasttt
Answer:
B
Explanation:
Hope this helps! sorry if incorrect
Which hand is negatively changed?
A.
B.
C.
D.
Answer:
I think B
Explanation:
There are more negative ions than positive ions
What physical property describes the ability of a substance to dissolve?
Answer:
solubility
Explanation:
A chemical engineer must calculate the maximum safe operating temperature of a high-pressure gas reaction vessel. The vessel is a stainless-steel cylinder that measures 39.0cm wide and 46.8cm high. The maximum safe pressure inside the vessel has been measured to be 5.30MPa. For a certain reaction the vessel may contain up to 7.20kg of sulfur hexafluoride gas. Calculate the maximum safe operating temperature the engineer should recommend for this reaction. Write your answer in degrees Celsius. Round your answer to 3 significant digits.
Answer:
Maximum safe operating temperature = 450 °C
Explanation:
First, the volume of the cylindrical vessel is determined using the formula:
v = πr²h
Radius, r, of stainless steel vessel = width or diameter / 2
r = 39.0 cm / 2 = 19.5 cm
height of vessel = 46.8 cm
volume of cylinder = 22/7 × 19.5² × 46.8 = 55929.343 cm³ = 0.05593 m³
Using the ideal gas equation to calculate the maximum safe temperature
PV = nRT
pressure, P = 5.30 MPa = 5.30 × 10⁶ Pa
R = 8.314 J/mol.K
n = mass of gas/ molar mass of gas
molar mass of SF₆ = 146 g/mol
mass of Sf₆ = 7.20 kg = 7200 g
n = 7200/146 = 49.315 moles
T = PV/nR
T = (5.30 × 10⁶ × 0.05593) / (49.315 × 8.314)
T = 722.98 K
T in °C = 714.98 - 273.15 = 449.83 °C
Therefore, maximum safe operating temperature = 450 °C
What is the pOH of .12 M HNO3.
If you have 600g of nitroglycerin, how many moles do you have?
help please
Answer:
600
Explanation:
there's 1 mole in every nitroglycerin
I think
Which statement would indicate the presence of an acid?
It tastes bitter..
It does not react with active metals.
It reacts with active metals to form a gas.
It does not change the color of litmus paper
Answer:
hey the answer is that it reacts with active metals to form a gas.
Explanation:
sorry i know this is late