Experiment 3 Quiz Sample Questions

Group of elements in the periodic table, reacting vigorously with water:

alkali metals

Color of litmus indicator in a base is:

Blue

Color of litmus in an acid is:

Red

Solid lead waste is disposed in:

Special waste can in hood

For the reaction CuSO4 × 5H2O → CuSO4 + 5H2O calculate theoretical of CuSO4 produced from 1.00g of pentahydrate (Cu = 64, S = 32, O = 16, H = 1)

0.64 g

For the reaction CuSO4 × 5H2O → CuSO4 + 5H2O calculate theoretical amount of water produced from 1.00g of pentahydrate (Cu = 64, S = 32, O = 16, H = 1)

0.36g

For the reaction 2Mg + O2 → 2MgO calculate the theoretical mass of product if 2.4g of magnesium was burnt in the oxygen (Mg = 24, O = 16)

4.0 g

Classify the reaction Zn + HNO3 = Zn(NO3)2 + H2O + NO2 according to the type:

redox or reduction/oxidation

Classify the reaction Zn(NO3)2 + Na2CO3 + H2O = ZnCO3 + CO2 + NaNO3 according to the type:

Metathesis

What law or principle will you try to prove in today’s experiment?

Principle of mass conservation

When doing experiment with combustion of magnesium, why do you need to lift the lid occasionally?

To allow air come into

Balance the reaction Mg + O2 → MgO and calculate mass of MgO in grams that you could get from 1.00g of Mg (Mg = 24, O = 16)

1.67

Balance the reaction Mg + O2 → MgO and calculate mass of O2 in grams used in reaction with 1.00g of Mg (Mg = 24, O = 16)

0.67

If reactants are solids and products are gases, the Principle of Conservation of Mass is:

Valid

For sodium metal, physical properties are: dissolving in mercury to form an alloy

True

For sodium metal, physical properties are: dissolving in water to form sodium hydroxide

False (this is a chemical property)

Principle of conservation of mass is not valid in vacuum

False

Principle of conservation of mass is not valid if reagents are solids and products are gases

False

Pb(NO3)2 + 2KI → PbI2 + 2KNO3 is an example of:

metathesis

Pb²⁺ (lead) in the salt Pb(NO3)2 is:

cation

Mass of the product after combustion of magnesium in air is higher than starting mass of magnesium, because of:

oxygen

Combustion of 1.0g of magnesium produces 1.6g magnesium oxide. Calculate amount of oxygen consumed, when 0.20g of magnesium was burned in air.

0.32 g

Mass of the product after heating of copper sulfate pentahydrate is lower than starting mass of solid, because of losing of:

water

Heating of 2.5g copper sulfate pentahydrate CuSO4 • 5H2O produces 1.6g of anhydrous copper sulfate CuSO4 and water. Calculate amount of water, in grams produced, if 1.0g of of CuSO4 • 5H2O was used

0.36g

Neutralization reaction is:

acid-base

Lead salts are toxic

True

Copper sulfate could exist as pentahydrate

True

Decomposition reaction leads to more than one product:

True

Crucible cleaning procedure includes:

heating in flame

Magnesium metal could evaporate, if it burning violently:

True

Ammonia vapors are:

dangerous to inhale

Sodium hydroxide is:

caustic