I will mark brainlist please help Answer and explain how you did that

20) How many grams of CaCI2 would be dissolved in 1.0 L of a 0.10 M solution of CaCI2?

21) How many grams of CaCl2 should be dissolved in 500.0 mL of water to make a 0.20M solution of CaCl2?

22) What mass of NaOH is on
250 mL of a 3.0M NaOH solution?

20) 2365 g

21) 22.39 grams.

22) 29.99 g

Explanation: 20) molarity is the no of moles of solute per unit volume.

We can calculate amount of CaCl2 required to prepare 0.1 M CaCl2 1000 ml solution.

we know that to prepare one ltr of 1 M solution of CaCl2 111 g required

Now consider x gram will require to prepare to

so that comparing above both condition

1000ml ×1M×X g=1000ml×0.1M×111g

X= 11.1 gram

X= 11.1 g of CaCl2

Hence 11.1 g of CaCl2 would be dissolved in 1.0L of a 0.100 M solution of CaCl2

21) How many moles of CaCl₂ in that solution?

;

;

.

What's the mass of that 0.20172 moles of CaCl₂?

Molar mass from a modern periodic table:

Ca- 40.078;

Cl- 35.45.

Molar mass of CaCl₂:

.

Mass of that 0.20172 moles of CaCl₂:

22) its a 3.0m solution so 1 litre of solution contains 3 moles of NaOH, 250ml of solution contains 0.25x39.9971 g/mol, so 250ml of this solution contains 0.75x39.9971=29.99g, or if you round it up 30.0g

answer:

the reaction is type of combination reaction.

explanation:

on the product side, there are 2 molecules of bonded to fe   which means one atom of fe are combined two molecules of . so, balanced chemical equation becomes :

this reaction follows the reaction type of combination reaction. a combination reaction is defined as chemical reaction in which reactants combines together to form a single product.

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.