Question

1. what type of chemical reaction took place when you mixed lead (ii) nitrate and potassium iodide? (hint: consider the known reactants. what kind of compounds are they?) /1t
2. write a skeletal chemical equation of the reaction of lead (ii) nitrate with potassium iodide, then balance it. /3t
3. what was the sum of the masses of lead (ii) nitrate and potassium iodide? /1t
4. how did the sum of the masses of lead (ii) nitrate and potassium iodide compare to the mass after the chemical reaction? were the masses equal or different? (there may be slight inaccuracies due to the limitations of the scale and slight differences in the beakers themselves).

is your answer to 5. supported by the law of conservation of mass? explain.
when you mixed acetic acid and sodium bicarbonate, what was the evidence of a chemical change?
what type of chemical reaction took place when you mixed acetic acid and sodium bicarbonate?
fill in the blanks to complete the chemical equation below: hc₂h₃o₂ + nahco₃ → ______+ h₂o + co₂(g)
what was the sum of the masses of acetic acid and sodium bicarbonate?
how did the sum of the masses acetic acid and sodium bicarbonate compare to the mass after the reaction? were the masses equal or different?
is your answer to 11. supported by the law of conservation of mass? if not, discuss whether the experimental design. (hint: refer to your answer to 7. and the chemical equation from)

Explanation:

Step1: Identify reaction type for lead (II) nitrate and potassium iodide

This is a double - displacement reaction as the cations and anions of the two reactants switch places. The reactants lead (II) nitrate ($Pb(NO_3)_2$) and potassium iodide ($KI$) are ionic compounds.

Step2: Write skeletal chemical equation

$Pb(NO_3)_2+KI
ightarrow PbI_2 + KNO_3$

Step3: Balance the equation

By adjusting the coefficients, we get $Pb(NO_3)_2 + 2KI
ightarrow PbI_2+2KNO_3$

Step4: Consider law of conservation of mass for lead (II) nitrate and potassium iodide reaction

According to the law of conservation of mass, in a closed - system chemical reaction, the sum of the masses of the reactants should be equal to the sum of the masses of the products. So the sum of the masses of lead (II) nitrate and potassium iodide before the reaction should be equal to the sum of the masses of lead (II) iodide and potassium nitrate after the reaction, ignoring minor experimental errors.

Step5: Identify reaction type for acetic acid and sodium bicarbonate

This is an acid - base reaction (specifically a gas - evolution reaction as carbon dioxide gas is produced). Acetic acid ($HC_2H_3O_2$) is an acid and sodium bicarbonate ($NaHCO_3$) is a base.

Step6: Complete chemical equation for acetic acid and sodium bicarbonate

$HC_2H_3O_2+NaHCO_3
ightarrow NaC_2H_3O_2+H_2O + CO_2(g)$

Step7: Consider law of conservation of mass for acetic acid and sodium bicarbonate reaction

Again, in a closed - system, the sum of the masses of acetic acid and sodium bicarbonate before the reaction should be equal to the sum of the masses of sodium acetate, water and carbon dioxide after the reaction, within the limits of experimental error. Evidence of a chemical change when mixing acetic acid and sodium bicarbonate is the production of carbon dioxide gas (bubbling).

Answer:

1. Double - displacement reaction; reactants are ionic compounds.
2. $Pb(NO_3)_2 + 2KI

ightarrow PbI_2+2KNO_3$

1. As above.
2. They should be equal according to the law of conservation of mass (ignoring experimental errors).
3. Equal; supported by the law of conservation of mass.
4. Acid - base (gas - evolution) reaction.
5. $NaC_2H_3O_2$
6. They should be equal according to the law of conservation of mass (ignoring experimental errors).
7. Equal; supported by the law of conservation of mass. Evidence of chemical change is gas production (bubbling).