Presentation is loading. Please wait.

Presentation is loading. Please wait.

What is the % composition of carbon in benzene (C 6 H 6 )? 2 slide.

Similar presentations


Presentation on theme: "What is the % composition of carbon in benzene (C 6 H 6 )? 2 slide."— Presentation transcript:

1 What is the % composition of carbon in benzene (C 6 H 6 )? 2 slide

2 Total mass of carbon/Total mass of compound 92%

3 How many grams of hydrogen are present in a 10.0 g sample of benzene (C 6 H 6 )? 2 slides

4 1) 8% Hydrogen 2) 0.08 x 10.0 g = g

5 What is the empirical formula for a compound that is 44% C, 26% N, & 30% O? 3 slides

6 1) Assume g, so % is changed to grams. 2) Convert each to moles by dividing by molar mass. 3) Divide each mole quantity by smallest mole quantity. (Rounding may occur.) C 2 NO

7 A compound has the empirical formula CH 2 O and molar mass of g. What is its molecular formula? 3 slides

8 1) Mass of CH 2 O = 30 g/mol 2) 120/30 = 4 3) 4(CH 2 O) = C4H8O4C4H8O4

9 What is the molarity of a solution that contains g KCl in 250 mL? 3 slides

10 1) Convert mass to moles g KCl x (1 mol/74.4 g) = 1.40 mol KCl 2) Convert mL volume to L 250 mL x (1 L/1000 mL) = 0.25 L 3) Divide moles/volume = 5.67 M

11 What mass of KCl is dissolved in mL to produce 2.50 M solution? 3 slides

12 1) Convert mL volume to L ( L) 2) Solve for moles L x (2.50 mol/L) = 1.25 mol 3) Convert moles to grams 1.25 mol x (74.4 g/mol) = 93 g

13 How many moles of CO 2 are in 22.0 g? 2 slides

14 22.0 g x (1 mol/44.0 g) = mol

15 How many moles of O 2 are in 5.6 L? 2 slides

16 5.6 L x (1 mol/22.4 L) = 0.25 mol

17 What is the volume occupied by 56.0 g of N 2 ? 3 slides

18 56.0 g x (1 mol/28.0 g) x (22.4 L/mol) = 44.8 L

19 What is the density of O 2 ? 2 slides

20 32.0 g/ 22.4 L = 1.43 g/L

21 What is the molar mass of a gas that has a density of 2.25 g/L? 2 slides

22 (22.4 L/1 mol) x (2.25 g/L) = 50.4 g/mol

23 Use the following reaction: 4NH 3 + 3O 2 2N 2 + 6H 2 O How many moles of oxygen, with excess ammonia, can produce 4 moles of nitrogen? 2 slides

24 4 mol N 2 x (3 mol O 2 /2 mol N 2 ) = 6 mol O 2

25 Use the following reaction: 4NH 3 + 3O 2 2N 2 + 6H 2 O How many grams of ammonia are needed to produce 14.0 g of N 2 ? 3 slides

26 14.0 g N 2 x (1 mol N 2 /28 g) x (4 mol NH 3 /2 mol N 2 ) x (17 g/1 mol) = 17.0 g

27 Use the following reaction: 4NH 3 + 3O 2 2N 2 + 6H 2 O How many grams of water are produced from 44.8 L of O 2 ? 4 slides

28 44.8 L x (1 mol O 2 /22.4 L) x (6 mol H 2 O/3 mol O 2 ) x (18 g H 2 O/1 mol) = 72.0 g

29 Use the following reaction: 4NH 3 + 3O 2 2N 2 + 6H 2 O If there are 5.00 moles of ammonia and 5.00 moles of oxygen, how many moles of nitrogen are produced? 4 slides

30 1) 5.00 moles of each reactant is what you have 2) 5.00 mol NH 3 x (3 mol O 2 /4 mol NH 3 ) = 3.75 mol O 2 is what I need 3) O 2 : have (5.00 mol) > need (3.75 mol), so NH 3 is limiting reactant 4) 5.00 mol NH 3 x (2 mol N 2 / 4 mol NH 3 ) = 2.50 mol N 2

31 Use the following reaction: 4NH 3 + 3O 2 2N 2 + 6H 2 O If excess oxygen reacts with 3.00 mol NH 3, what is the theoretical yield of H 2 O? 3 slides

32 3.00 mol NH 3 x (6 mol H 2 O/4 mol NH 3 ) x (18 g/mol) = 81.0 g

33 If 70.0 g of water is produced, what is the percent yield? 2 slides

34 1) 70.0 g = actual yield 2) 81.0 g = theoretical yield 3) [actual/theoretical] x 100 = 86.4 %

35 Use the following reaction: Fe + 2HCl FeCl 2 + H 2 If 20 atoms of iron are dropped into a beaker containing hydrochloric acid, how many molecules of hydrogen would be produced? 2 slides

36 20 Fe atoms x (1 H 2 molecule/1 Fe atom) = 20 H 2 molecules


Download ppt "What is the % composition of carbon in benzene (C 6 H 6 )? 2 slide."

Similar presentations


Ads by Google