Answer:
Option C. Na⁺(aq) and Cl¯(aq)
Explanation:
From the question given above, we obtained the following:
Na₂SO₄(aq) + CaCl₂(aq) —> CaSO₄(s) + 2NaCl(aq)
Ionic Equation:
2Na⁺(aq) + SO₄²¯(aq) + Ca²⁺(aq) + 2Cl¯(aq) —> CaSO₄(s) + 2Na⁺(aq) + 2Cl¯(aq)
From the ionic equation above, we can see that Na⁺(aq) and Cl¯(aq) are present on both side of the equation.
Therefore, Na⁺(aq) and Cl¯(aq) are the spectator ions because they did not participate directly in the reaction.
Answer: 1. Vinegar, used in the kitchen, is a liquid containing 3-6% acetic acid. It is used in pickles and in many food preparations.
2. Lemon and orange juice contains citric acid. Citric acid is used in the preparation of effervescent salts and as a food preservative.
3. Acids have been put to many uses in industry. Nitric acid and sulphuric acid are used in the manufacture of fertilizers, dyes, paints, drugs and explosives.
4. Sulphuric acid is used in batteries, which are used in cars, etc. Tannic acid is used in the manufacture of ink and leather.
5. Hydrochloric acid is used to make aqua regia, which is used to dissolve noble metals such as gold and platinum.
6. Sulphuric acid is used in manufacturing fertilizers such as super phosphate, ammonium sulpahte etc.
Answer : The correct option is, (D) CO₂, BCl₃, and Fe³⁺
Explanation :
According to the Lewis concept, an acid is defined as a substance that accepts electron pairs and base is defined as a substance which donates electron pairs.
(a) 
It is a Lewis-acid because it can accepts electron pairs.
(b) 
It is not a Lewis-acid because it can not accepts electron pairs but it is a base because it can donates and accept hydrogen ion.
(c) 
It is a Lewis-acid because it can accepts electron pairs because it has an incomplete octet and an empty 2p orbital.
(d) 
It is a Lewis-acid because it can accepts electron pairs.
Hence, the ions which behave as Lewis acids are, CO₂, BCl₃, and Fe³⁺
Answer: 122 moles
Procedure:
1) Convert all the units to the same unit
2) mass of a penny = 2.50 g
3) mass of the Moon = 7.35 * 10^22 kg (I had to arrage your numbers because it was wrong).
=> 7.35 * 10^22 kg * 1000 g / kg = 7.35 * 10^ 25 g.
4) find how many times the mass of a penny is contained in the mass of the Moon.
You have to divide the mass of the Moon by the mass of a penny
7.35 * 10^ 25 g / 2.50 g = 2.94 * 10^25 pennies
That means that 2.94 * 10^ 25 pennies have the mass of the Moon, which you can check by mulitiplying the mass of one penny times the number ob pennies: 2.50 g * 2.94 * 10^25 = 7.35 * 10^25.
5) Convert the number of pennies into mole unit. That is using Avogadros's number: 6.022 * 10^ 23
7.35 * 10^ 25 penny * 1 mol / (6.022 * 10^ 23 penny) = 1.22* 10^ 2 mole = 122 mol.
Answer: 122 mol
The mass of water equals the mass of the hydrate minus the mass of the anhydrite 4.9 G -2.9 G equals 2.0 G of water moles of water equals the mass of water/the molar mass of water 2.0 GH20/18 G/MOLHTO equals 0.11 Moles H20
