All categories

3 years ago

Give the correct thermochemical equations for a (cacl2+h2o) pack and (nh4no3+h2o) pack.

Chemistry

1 answer:

Umnica [9.8K]3 years ago

7 0

In a pack of CaCl2 and H2O, hydrolysis of Ca+2 will occur

This will result in formation of Ca(OH)2.

The reaction is exothermic in nature

so the balanced thermo-chemical equation will be

CaCl2(aq) + H2O (l) ---> Ca(OH)2 + 2HCl + Heat

In a pack of NH4NO3 and H2O hydrolysis of NH4+ will occur as

NH4NO3 (aq) + H2O(l) + Heat ---> NH4OH(aq) + HNO3 (aq)

It is an endothermic reaction

You might be interested in

For the closed system below: Cu(s) + 2Ag+(aq) 2Ag(s) + Cu2+(aq) How would you know if the system is at equilibrium?

zaharov [31]

For the chemical reactiom to be at equilibrium:
1- The rate of forward reaction must be equal to the rate of the reverse reaction.
2- The mass of EACH element must be equal before and after the reaction (no NET change in mass), otherwise the equilibrium will shift.

Important note: you need to check the mass of each element before and after the reaction (i.e, reactants side and products side) and the not the mass of the system as a whole. This is because the mass of the whole system will be preserved whether the system is at equilibrium or not (this is the fundamental law of mass conservation)

5 0

3 years ago

"Conservation of energy" refers to the fact that _____.

Agata [3.3K]

Answer: Option (b) is the correct answer.

Explanation:

According to the law of conservation of energy, it is known that energy can neither be created nor it can be destroyed.

But energy can be changed from one form to another.

Whereas entropy is the degree of randomness present within the molecules of a substance or object.

For example, gas molecules are able to move rapidly so, they have more entropy as compared to solid and liquid substances.

According to second law of thermodynamics, entropy of the system is always increasing.

Thus, we can conclude that "Conservation of energy" refers to the fact that energy cannot be created or destroyed but can be converted from one form to another.

8 0

3 years ago

To what volume in millimeters must 50.0 mL of 18.0 M H2SO4 be diluted to obtain 4.35 M H2SO4?

poizon [28]

We know that to relate solutions of with the factors of molarity and volume, we can use the equation: $M_{1} V_{1} = M_{2} V_{2}$

**NOTE: The volume as indicated in this question is defined in L, not mL, so that conversion must be made. However it is 1000 mL = 1 L.

So now we can assign values to these variables. Let us say that the 18 M $H_{2} SO_{4}$ is the left side of the equation. Then we have:

$(18 M)(0.050 L)=(4.35M) V_{2}$

We can then solve for $V_{2}$ :

$V_{2}= \frac{(18M)(0.05L)}{4.35M}$ and $V_{2} =0.21 L$ or $210 mL$

We now know that the total amount of volume of the 4.35 M solution will be 210 mL. This is assuming that the entirety of the 50 mL of 18 M is used and the rest (160 mL) of water is then added.

7 0

3 years ago

Which word completes the blank in the following statement?

Dvinal [7]

The answer should be an electrical circut
i think thats how you spell it

8 0

3 years ago

How mant grams are there in 7.15 x 10^24 molecules of water?

worty [1.4K]

Answer:

B. 214.02

Explanation:

1 mol of water weighs 18.015 gm and contains 6.023 × 10²³ molecules

From question, We have 7.15 × 10²⁴ molecules

Dividing we get (7.15 × 10 ²⁴) ÷ ( 6.023 × 10²³) = 11.871 molecules

Now, Weight of water = 11.871 × 18.015 = 213.85 which is nearer to option B

4 0

2 years ago

Read 2 more answers