Discovering Design with Chemistry Test 7

How many moles are found in a 100.0g sample of CuF(sub)2?

0.9874 moles

The decomposition of KClO(sub)3 occurs as follows: 2KClO(sub)3 --> 2KCl + 3O(sub)2 How many moles of oxygen are formed if 141g of KClO(sub)3 decompose?

1.15 moles KClO(sub)3, 1.73 moles O(sub)2

A chemical reaction produces 11.8 moles of tin (Sn) atoms. How many grams of tin are made?

1.40 x 10^3 grams

What is the mass (in grams) of 169 moles of CF(sub)4?

14,900 grams15.2 moles CO

How many molecules are in a 671g sample of Co(sub)2?

15.2 moles CO(sub)2, 9.15 x 10^24 molecules CO(sub)2

When Sodium is but into water, it quickly reacts according to the following equation: 2Na (s) + 2H(sub)O --> 2NaOH (aq) + H(sub)2 (g) If 4.52 moles of Na react with an excess of water, how many grams of H(sub)2 are formed?

2.26 moles H(sub)2, 4.57 grams H(sub)2

The combustion of propane, C(sub)3H(sub)8, occurs according to this chemical equation: C(sub)3H(sub)8 (g) + 5O(sub)2 --> 3CO(sub)2 (g) + 4H(sub)2O (g) If 901 moles of C(sub)3H(sub)8 are burned in excess oxygen, how many moles of CO(sub)2 are formed?

2.70 x 10^3 moles

If I have 6.02 x 10^23 atoms of silicon, how many grams of silicon do I have?

28.09 grams of silicon

Fill in the blanks for the following reaction: 2Al (s) + 3Br(sub)2 (g) --> AlBr(sub)3 _______ moles of Al(s) react with _______ moles of Br(sub)2 to produce 2 moles of AlBr(sub)3.

2;3

A chemist reacts 150.0 grams of HCl with an excess of MnO(sub)2. If the following reaction occurs: MnO(sub)2 + 4Hcl --> McCl(sub)2 + 2H(sub)2O + Cl(sub)2 How many grams of MnCl(sub)2 are formed?

4.114 moles HClO, 1.029 moles MnCl(sub)2, 129.5g MnCl(sub)2

Turpentine, C(sub)10H(sub)16, can react with chlorine gas to make carbon and hydrogen monochloride: C(sub)10H(sub)16 (l) + 8Cl(sub)2 (g) --> 10C (s) + 16HCl (g) Suppose a chemist runs this reaction and makes 569g of carbon. How many grams of turpentine were consumed?

47.4 moles C, 4.74 moles C(sub)10H(sub)16, 646g C(sub)10H(sub)16

A chemist makes aluminum sulfide according to the following chemical equation: 16Al (s) + 3S(sub)8 (s) --> 8Al(sub)2S(sub)3 He runs the reaction and finds that in the end, lots of Al(sub)3S(sub)3 is made, and the only other chemical present is S(sub)8. What is the limiting reactant?

Al

Hydrated CoCl(sub)2 is deep purple in color. After being heated for a long time, it turns into its anhydrous form, why is sky blue. Is this a chemical or physical change?

Physical change

Hydrated sodium sulfate has a chemical formula of Na(sub)2SO(sub)4 * 10H(sub)2O a. What is the chemical formula of the anhydrous form of the same compound? b. How many water molecules are there for every one Na(sub)2SO(sub)4? c. A chemist starts out with 15.0g of anhydrous Na(sub)2SO(sub)4. If she hydrates the compound completely, how many grams of water will be added to the sample?

a. Na(sub)2SO(sub)4 b. 10 c. 0.106 moles Na(sub)2SO(sub)4, 1.06 H(sub)2O, 19.1 H(sub)2O

Define: a. Hygroscopic b. Limiting reactant

a. Readily absorbs moisture, even from the atmosphere b. The reactant that runs out first, limiting the amount of product made

Suppose you have the following samples: a. 24.31g of magnesium b. 9.01g of beryllium c. 5.10g of lithium d. 12.01g of carbon Which sample has the fewest number of atoms?

c.