How does particle model explain a change of state of matter?

Answer the following questions based on the reaction below: NaOH(aq) + KHP(s) --> NaKP(aq)+H2O(I)

Natali [406]

Answer:

a) 1.44g

b) 77.3%

Explanation:

1. Chemical balanced equation (given)

$NaOH(aq)+ KHP(s)\rightarrow NaKP(aq)+H_2O(l)$

2. Mole ratio

$1molNaOH(aq):1molKHP(s)$

This is, 1 mol of NaOH will reacts with 1 mol of KHP.

3. Find the number of moles in 72.14 mL of the base

$Molarity=\text{number of moles of solute}/\text{volume of solution in liters}$

$\text{Volume of solution}=72.14mL=0.07214liters$

$\text{Number of moles of NaOH}=0.0978M\times 0.07214liter=0.007055mol$

4. Find the number of grams of KHP that reacted

The number of moles of KHP that reacted is equal to the number of moles of NaOH, 0.007055 mol

Convert moles to grams:

mass = number moles × molar mass = 0.007055mol × 204.23g/mol

mass = 1.4408 g.

You have to round to 3 significant figures: 1.44 g (because the molarity is given with 3 significant figures).

5. Find the percentage of KHP in the sample

The percentage is how much of the substance is in 100 parts of the sample.

The formula is:

% = (mass of substance / mass of sample) × 100

% = (1.4408g/ 1.864g) × 100 = 77.3%

7 0

2 years ago

1. How will you differentiate physical from chemical change in terms of the

Tpy6a [65]

Answer:

In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.

3 0

3 years ago

Which of the following shows how rate depends on concentrations of reactants?

Katarina [22]

Answer:

Rate = k(A)m(B)n

Explanation:

A.P.E.X.

6 0

2 years ago

Is it possible for two different compounds to be made from the exact same two elements? Why or why not? With a limited number of

daser333 [38]

Answer:

Yes. The two elements can combine to form different compounds.

Explanation:

Two elements can combine at different ratios.

Consider CO and CO₂. Both are made from carbon and oxygen. However, C and O combine at a 1:1 ratio in CO but at a 1:2 ratio in CO₂. CO is a fuel; it burns in the air. CO₂ does not burn in the air; it is used to put out fires and is found in extinguishers. CO and CO₂ are two distinct compounds.

There are many ways for the elements to combine with each other. As a result, the first twenty elements on the periodic table alone can produce a large number of compounds.

6 0

2 years ago

Ammonia chemically reacts with oxygen gas to produce nitric oxide and water . What mass of water is produced by the reaction of

Kay [80]

Full Question:

Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. What mass of water is produced by the reaction of 7.7g of ammonia?

Be sure your answer has the correct number of significant digits.

Answer:

12.23g ≈ 12g (2 s.f)

Explanation:

Ammonia chemically reacts with oxygen gas to produce nitric oxide and water. The balanced chemical reaction is given as:

4 NH3 + 5 O2 -------> 4 NO + 6 H2O

From the reaction;

4 mole of ammonia reacts to produce 6 moles of water

From the question;

Moles = mass / molar mass

From the question;

moles of ammonia = mass / molar mass = 7.7 / 17 = 0.4529moles

Number of moles of water produced;

4 = 6

0.4529 = x

x = (0.4529 * 6 ) / 4

x = 0.67935moles

Mass of water = moles * molar mass = 0.67935 * 18 = 12.23g ≈ 12g (2 s.f)

4 0

2 years ago