Exam 1 Review <3

Fun, not so fun idk

100

How do you round to the correct number of significant figures when multiplying/dividing two numbers?

Adding/subtracting?

*/÷ : the answer has the same number of sig figs as the original number with the fewest sig figs

+/- : The answer has the same number of sig figs as the number with the fewest DECIMAL places

200

Conventional Notation for:

Kilo, centi, milli and micro

1000, 0.01, 0.001, 0.000001

300

When are trailing zeros significant? 

Leading zeros?

(trailing) When there is a decimal anywhere in the number.

(leading) NEVER

400

Give the formula (including charges) for the following polyatomic ions:

Ammonium, Acetate, Hydroxide, Chlorate, Nitrate

NH₄⁺, CH₃COO^-, OH^-, ClO₃^-, NO₃​^-​​​

500

Give the formula (including charges) for the following polyatomic ions:

Permanganate, Hydronium, Carbonate, Bicarbonate, Dichromate, Phosphate, Sulfate

MnO₄^-, H₃O⁺, CO₃^2-, HCO₃^-, Cr₂O₇^2-, PO₄^3-, SO₄^2-

Ionic & Covalent

100

Dihydrogen monoxide

H₂O

200

Ammonium sulfate

(NH₄)₂SO₄

300

Na₂CO₃

Sodium carbonate

400

FeCl₃

Iron (III) chloride

500

CoBr₂

Cobalt (II) bromide

Limiting Reagent & Yields

100

 If you have 5 mol H₂ and 2 mol N₂, what is the limiting reagent in the reaction below?

3 H₂(g) + N₂ (g) → 2 NH₃ (g)

H₂

200

If 33.6 g of NO and 26.9 g of O₂ react together, what is the mass in grams of NO₂ that can be formed via the reaction below?

2 NO (g) + O₂ (g) → 2 NO₂ (g)

51.06 grams NO₂

300

In this reaction: Mg (s) + I₂ (s) → MgI₂ (s)

If 4.56 moles of Mg react with 5.98 moles of I₂, and 3.79 moles of MgI₂ form, what is the percent yield?

63.4%

400

You have 4.3 mol Xe and 3.0 mol F₂, but when you carry out the reaction you end up with only 1.35 mol XeF₄. What is the percent yield of this experiment?

Xe(g) + 2 F₂ (g) → XeF₄ (g)

90%

500

Calculate the theoretical yield in grams of AlI₃ from the complete reaction of 18.3 grams of Al according to the following BALANCED equation:

2Al (s) + 3I₂ (s) → 2AlI₃ (s)

277 grams AlI₃

Balancing Equations

100

C₃H₈ + O₂ → H₂O + CO₂

C₃H₈ + 5O₂ → 4H₂O + 3CO₂

200

Li₂Se (s) + SO₂ (g) 

SSe₂ (g) + Li₂O (s)

2Li₂Se (s) + SO₂ (g) 

SSe₂ (g) + 2Li₂O (s)

300

AlBr₃ + K₂SO₄ → KBr + Al₂(SO₄)₃

2AlBr₃ + 3K₂SO₄ → 6KBr + Al₂(SO₄)₃

400

HClO₄ + P₄O₁₀→ H₃PO₄ + Cl₂O₇

12HClO₄ + P₄O₁₀ → 4H₃PO₄ + 6Cl₂O₇

500

FeS₂ + O₂ → Fe₂O₃ + SO₂

4FeS₂ + 11O₂ → 2Fe₂O₃ + 8SO₂

Applied Concepts

100

Calculate the moles of BCl₃ that will be required to produce 945 grams of B₂H₆?

BCl₃(g) + LiAlH₄(s) → B₂H₆(g) + LiAlCl₄(s)

BALANCED equation:

4BCl₃(g) + 3LiAlH₄(s) → 2B₂H₆(g) + 3LiAlCl₄(s)

68.3 mols

200

Determine the quantity of nitrogen atoms in 15.0 grams of Pb(NO₂)₂

6.04 x 10²²

300

Consider the chemical equation:

H₂(g) + N₂(g) → NH₃(g)

If 46.8 g H₂ and 179.4 g N₂ are mixed to form NH₃, which of the following substances is the limiting reactant?

BALANCED equation:

3H₂(g) + N₂(g) → 2NH₃(g)

Limiting Reagent: Nitrogen (N₂)

400

Mercury(II) nitrate is a compound formerly used to treat fur to make felt for hats. It can also cause a psychological illness, which is where the phrase 'mad as a hatter' originated. Mercury(II) nitrate is synthesized by the reaction of mercury metal with hot concentrated nitric acid:

Hg(l) + HNO₃(aq) → Hg(NO₃)₂ + H₂(g)

What mass in grams of mercury metal would be required to form 6.55 grams of mercury(II) nitrate?

BALANCED equation:

Hg(l) + 2 HNO₃(aq) → Hg(NO₃)₂ + H₂(g)

4.05 grams Hg

500

If 25.0 g of NH₃ and 45.0 g of O₂ react in the following reaction, what is the mass in grams of NO that will be formed?

NH₃ (g) + O₂ (g) → NO (g) + H₂O (g)

BALANCED equation:

4 NH₃ (g) + 5 O₂ (g) → 4 NO (g) + 6 H₂O (g)

Mass: 33.8 g NO