<u>Answer:</u> The initial pH of the HCl solution is 3
<u>Explanation:</u>
To calculate the concentration of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is HCl
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

1 mole of HCl produces 1 mole of
ions and 1 mole of
ions
To calculate the pH of the solution, we use the equation:
![pH=-\log[H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5BH%5E%2B%5D)
We are given:
![[H^+]=0.001M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D0.001M)
Putting values in above equation, we get:

Hence, the initial pH of the HCl solution is 3
The mass of sodium sulphate, Na₂SO₄, required to prepare the solution is 10.65 g
<h3>How to determine the mole of sodium sulphate Na₂SO₄</h3>
- Volume = 250 mL = 250 / 1000 = 0.25 L
- Molarity = 0.3 M
Mole = Molarity x Volume
Mole of Na₂SO₄ = 0.3 × 0.25
Mole of Na₂SO₄ = 0.075 mole
<h3>How to determine the mass of sodium sulphate Na₂SO₄</h3>
- Molar mass of Na₂SO₄ = 142.05 g/mol
- Mole of Na₂SO₄ = 0.075 mole
Mass = mole × molar mass
Mass of Na₂SO₄ = 0.075 × 142.05
Mass of Na₂SO₄ = 10.65 g
Thus, 10.65 g of Na₂SO₄ is needed to prepare the solution.
Learn more about molarity:
brainly.com/question/15370276
Answer is: c. It is incorrect because sodium phosphate is a compound that has a single composition.
Sodium phosphate is chemical compound composed of atoms connected with chemical bonds.
Pure substance is made of only one type of atom (element) or only one type of molecule (compound), it has definite and constant composition with distinct chemical properties.
Pure substances can be separated chemically, not physically, that is difference between pure substances and mixtures.
Answer:Atomic theory established that all matter is made of tiny particles, a discovery that led to amazing scientific breakthroughs in areas from modern chemistry to nuclear energy.
Explanation:Atomic theory is the scientific theory that matter is composed of particles called atoms. Atomic theory traces its origins to an ancient philosophical tradition known as atomism.
Answer:
The final temperature was 612 °C
Explanation:
Charles's law relates the volume and temperature of a certain amount of ideal gas, maintained at a constant pressure, using a constant of direct proportionality. In this law, Charles says that at constant pressure, as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases. That is, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the ratio between volume and temperature will always have the same value:

When you want to study two different states, an initial and a final one of a gas and evaluate the change in volume as a function of temperature or vice versa, you can use the expression:

In this case:
- V1= 5.76 L
- T1= 22 °C= 295 °K (Being 0°C=273°K)
- V2=17.28 L
- T2=?
Replacing:

Solving:

T2= 885 °K = 612 °C
<u><em>The final temperature was 612 °C</em></u>