Explain the relation between muscles, ATP energy, and the calcium ion

What is the % concentration (m/v) of a solution prepared by dissolving 10.0g of NaOH in enough water to make 225mL of solution?

What is the resonance structure for SeO₂ and how is the bond lenght compared to an isolated single or double bond?

Please show all work so that i can get a better understanding

A.) Estimate ΔG°_rxn for the following reaction at 449.0 K.

CH₂O(g) + 2 H₂(g) → CH₄(g) + H₂O(g) ΔH°= -94.9 kJ; ΔS°= -224.2 J/K

B.) Which of the following statements is TRUE?

C.) Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.

2 Hg(g) + O₂(g) → 2 HgO(s) ΔG° = -180.8 kJ

P(Hg) = 0.025 atm, P(O₂) = 0.037 atm

D.)Above what temperature does the following reaction become nonspontaneous?

FeO(s) + CO(g) → CO₂(g) + Fe(s) ΔH= -11.0 kJ; ΔS = -17.4 J/K

1. explain the difference between heat of neutralization and enthalpy of neutralization.

2. You mix 50.0 mL of a weak monoprotic acid with 50.0 mL of NaOH solution in a coffee cup calorimeter. Both solutions (and the calorimeter) were initially at 22.0^OC. The final temperature of the neutralization reaction was determined to be 22.5^OC.

a)What is the total amount of heat evolved in this reaction? Show all work. (3 points)

b) If 0.135 moles of the monoprotic acid were neutralized in this reaction, what is the molar heat of neutralization (enthalpy) for this reaction? (3 points)

3. Imagine you are at a local water park on a hot summer day and your feet begin to get hot from the cement.Looking ahead, you notice that there are two paths you can take to your favorite waterslide. One path is comprised of sand while the other path consists of water.You opt for the water path because you know it will be cooler on your feet.Assuming that both paths were exposed to the same heatsource (the sun) and that both paths have the same mass, explain why water does not get as hot as sand.

#32 Calculate the pH at the equivalent point for the titration of 0.10M NH3 by 0.10M perchloric acid. (For NH3, pKb=4.74, hint: consider the change in volume before and after reaction)

You mix a 116.5 mL sample of a solution that is 0.0127 M in NiCl2 with a 174.5 mL sample of a solution that is 0.220 M in NH3. After the solution reaches equilibrium, what concentration of Ni2+(aq) remains? (Formation constant is Kf=2.0×108.) Express your answer with the appropriate units.

Q1)

Suppose that 23 g of each of the following substances is initially at 27.0 ∘C. What is the final temperature of each substance upon absorbing 2.45 kJ of heat?

Part A

gold

Part B

silver

Part C

aluminum

Part D

water

Q2) A 32.5 g iron rod, initially at 22.7 ∘C, is submerged into an unknown mass of water at 63.1 ∘C, in an insulated container. The final temperature of the mixture upon reaching thermal equilibrium is58.4 ∘C.

What is the mass of the water?

Express your answer to two significant figures and include the appropriate units.

Q3)Instant cold packs, often used to ice athletic injuries on the field, contain ammonium nitrate and water separated by a thin plastic divider. When the divider is broken, the ammonium nitrate dissolves according to the following endothermic reaction:
NH4NO3(s)→NH+4(aq)+NO−3(aq)
In order to measure the enthalpy change for this reaction, 1.25 g of NH4NO3 is dissolved in enough water to make 25.0 mL of solution. The initial temperature is 25.8 ∘C and the final temperature (after the solid dissolves) is 21.9 ∘C.

Part A

Calculate the change in enthalpy for the reaction in kilojoules per mole. (Use 1.0g/mL as the density of the solution and 4.18J/g⋅∘C as the specific heat capacity.)

Express your answer to two significant figures and include the appropriate units.

Q4)Zinc metal reacts with hydrochloric acid according to the following balanced equation.

Zn(s)+2HCl(aq)→ZnCl2(aq)+H2(g)

When 0.107 g of Zn(s) is combined with enough HCl to make 54.4 mL of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 22.3 ∘C to 24.3 ∘C.

Part A

Find ΔHrxn for this reaction as written. (Use 1.0 g/mL for the density of the solution and 4.18 J/g⋅∘C as the specific heat capacity.)

How many mol Al2O3 made if:

4 Al (s) + 3 O2 (g) -> 2 Al2O3 (s) ; 16 mol Al , 13 mol O2

* Al is limited reagent

1. Based on the values you recorded during the lab session for volume of methanol and mass of NaOH, calculate the correct concentration of the resulting solution in units of molarity.

2. If the NaOH solid absorbed water from the atmosphere during this process (as described above), is the concentration you calculated in #1 too high or too low? Explain.

3. Based on the definition of “catalyst” you provided in your prelab, is the exact concentration of the NaOH/methanol solution critical to the stoichiometry of the transesterification reaction? Explain.

4. If you worked slowly in the preparation of the NaOH/methanol solution and the solid NaOH absorbed water from the atmosphere, how would the stoichiometry of the biodiesel synthesis be affected, if at all? Explain.

5. Any absorbed water discussed in question #4 would be present in the reaction mixture. Using your knowledge of intermolecular forces, in which product layer would the water most likely be found (biodiesel or glycerol)? Explain.

6. Based on your observations, compare the intermolecular forces of the food dye with the vegetable oil. Were they similar or different? How do you know?

7. Why was it unnecessary to clean the graduated cylinder between measuring the vegetable oil and then the NaOH/methanol solution in steps 7-8 of Part 2 in the procedure? Explain.

8. Referring to the respective intermolecular forces of the molecules, explain why glycerol forms a homogeneous mixture with water, but not biodiesel.

9. Using the final measured weight of glycerol, calculate the actual yield and percent yield for glycerol based on the theoretical yield you calculated as part of the pre-lab questions.

10. Identify a minimum of THREE potential sources of error for this experimental procedure and comment on how they could help explain (or not) you’re the percent yield of glycerol you calculated in question #8. Your comments should be thoughtful and you should explain how the error would impact your results.

Given an acid with a concentration of 0.4 M in a 1 liter solution, answer the following questions:

• What is the pH if pka = 4.76

• What is the pH after the addition of 0.2 mol NaOH (pka =4.76)?

• What is the ka of a solution with 0.65 M HA and 0.44 M A- (pH=6.0)

1. 20 mL of a 10 mg/L chloroform solution in water is placed in a 40 mL vial and sealed. After equilibrium is reached, the vial is opened and the chloroform concentration in the water is found to be 8.90 mg/L

a. Use material balance to find the Henry's constant, Hc. (dimensionless)

b. What is the concentration in the gas phase in the vial?

Use activity coefficients to calculate molar solubility of Zn(OH)₂ in

a) a mixture of 40.0mL of 0.250M KOH with 60.0mL de ZnCl₂ 0.0250M

b) mixture of 20mL 0.100M KOH and 50.0mL of 0.0250M ZnCl₂

c) K₂SO₄ 0.0300M M