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Mole, avogadro's number and laws of chemical combinations

Total questions: 21

Worksheet time: 1hrs 10mins

Name
Class
Date
1.

How many atoms are there in one mole of carbon?

a)

Avogador's number

b)

28000

c)

6.022x10^23

d)

A lot

2.

What is the mass of one mole of carbon atoms?

a)

20 g/mol

b)

16 g/mol

c)

4 g/mol

d)

12 g/mol

3.

What is the mass of one mole of carbon dioxide (CO2)?

C = 12g/mol

O = 16g/mol

a)

44 g/mol

b)

50 g/mol

c)

31 g/mol

d)

16 g/mol

4.

How many moles of sodium are there in 250 grams of sodium?


Remember Number of moles = mass / atomic mass

a)

10.86 moles

b)

10.86 atoms

c)

65.45x10^23 atoms

d)

6.45 atoms

5.

How many atoms are there in 5.0 grams of gold?

(same formula as before)

a)

0.25 atoms

b)

0.1528x10^23 atoms

c)

0.025 atoms

d)

none of the above

6.

What is the mass of one mole of water (H2O)?

a)

18 g/mol

b)

16 g/mol

c)

1 g/mol

d)

6.022x10^23 atoms

7.

The molar mass of CO2 is 44.01 g. Therefore, one mole of carbon dioxide has

a mass of _____ , and 0.500 mole has a mass of _____ .

a)

40 g and 12.2 g

b)

44.01 g and 22.0 g

c)

12 g/mol

d)

16 g/mol

8.

What is the mass of 6.02 × 1023 atoms of aluminum?

a)

1 g/mol

b)

27 g/mol

c)

20 g/mol

d)

13 g/mol

9.

Calculate the definite proportions for H2O

a)

11% of H and 89% of O

b)

50% of H and 50% of O

c)

20% of H and 80% of O

d)

15% of H and 85% of O

10.

Calculate the definite proportions of C2H6O

a)

52 % of C. 13% of H, 35% of O

b)

33.33% of C, 33.3% of H, 33.3% of O

c)

50% of C, 50% of O

d)

52 % of C. 13% of H, 35% of O

11.

Sodium chloride, NaCl, contains 39% Na (sodium) and 61% Cl (chloride) by mass. If you have a 150-g sample of NaCl, how many grams of sodium and chloride are there in the sample?

a)

10 grams of sodium and 91.5 grams of chloride

b)

39% of sodium and 61% of chloride

c)

58.5 grams of sodium and 91.5 grams of chloride

d)

58.5 grams of soidum and 10 grams o chloride

12.

What was important about the law of reciprocal proportions?

a)

It led to our understanding of stoichiometry today

b)

It helped scientists discover new compounds

c)

It helped scientists measure compound sizes

d)

It helped scientists create the periodic table

13.

Who discovered the law of reciprocal proportions?

a)

Jeremias Richter

b)

Benjamin Franklin

c)

Sir Isaac Newton

d)

John Dalton

14.

Two different compounds are formed by the elements carbon and oxygen. The first compound contains 42.9% by mass carbon and 57.1% by mass oxygen. The second compound contains 27.3% by mass carbon and 72.7% by mass oxygen. Show that the data are consistent with the Law of Multiple Proportions.

a)

I have no clue

b)

1 /2

c)

The multiple proportions law doesn't apply

d)

2.66 / 1.33 = 2 (ratio for oxygen)

15.

Prove the law of multiple propotions for NO and NO2

a)

It doesn't apply

b)

the ratio between both NO and NO2 is 2 , therefore the law applies

c)

Je ne sais pas

d)

Miss, neta no entiendo nada

16.

cual es el nombre del antagonista de la pelicula infinity war

a)

ultron

b)

thanos

c)

craneo rojo

d)

dr.doom

17.

cual es el ultimo personaje que muere en infinity war?

a)

groot

b)

capitan america

c)

spider-man

d)

iron-man

18.

cual fue la primera pelicula del universo cinematografico de marvel?

a)

iron-man

b)

capitan america:el primer vengador

c)

thor

d)

los vengadores

19.

cual de estos es ant-man

a)
b)
c)
d)
20.
Según el cuento de las Reliquias de la Muerte, el que posea la capa de la invisibilidad, la varita de saúco y la piedra de la resurrección se convertirá en... 
a)
señor de la muerte
b)
señor de las sombras
c)
amo de la oscuridad
d)
rey del poder
21.
¿En que fecha fue creado el colegio Hogwarts de magia y hechicería?
a)
El 19 de abril del 1240
b)
El 20 de enero del 990
c)
El 22 de noviembre del 991
d)
El 30 de agosto del 1100