Question

Valium (C16H13N2OCl) is a common sedative, with dosages rarely ever exceeding 10.0 mg. How many moles of valium would be in this maxmim dosage?

A. 2.85
B. 35.1
C. 3.51 x 10-2

D. 3.51 x 10-5

Silver salts have antimicrobial properties--they can kill bacteria by interfering with certain proteins. Silver nitrate used to be given in drop form to newborns to prevent them from contracting gonorrhea from infected mothers. How many oxygen atoms would be in 2.0 moles of silver nitrate?
A. 6.0
B. 6.022 x 1023

C. 3.61 x 1024

D. 1.20 x 1024

1.00 mole of O2 contains the same number of molecules as:

A. 0.667 mole of O3.

B. 2.00 mole of CH3CH2OH.

C. 1.00 mole of CH3CO2H.

D. All of these

The molecular formula for nicotine is C10H14N2. If an average cigarette contains 1.234 x 10-5 moles of nitrigen atoms from nicotine, how many moles of carbon are in the sample?

A. 1.234 x 10-25

B. 10
C. 2.468 x 10-6

D. 6.168 x 10-5

____ energy is the energy of motion.
A. kinetic
B. potential
C. electrical
D. chemical
E. none of the above

A certain reaction is exothermic. Therefore, the reverse of this same reaction must be a(n)
A. isothermal process.
B. exothermic process.
C. chemical change.
D. endothermic process.
E. none of the above

For a system at constant pressure, 12,400 calories of heat are released. This quantity of heat is equivalent to
A. 1.92 × 10-5 J

B. 1.24 × 104 J

C. 2.96 × 103 J

D. 5.19 × 104 J.

The Law of Conservation of Energy states which of the following?
A. none of these.
B. Potential energy is conserved.
C. Kinetic energy is conserved.
D. Energy cannot be converted from one form to another.

If I apply 0.108 kJ of energy in order to increase the temperature of a bar of gold from 30.0°C to 34.7°C, and the specific heat capacity of gold is 0.128 J/g°C, what is the mass the bar of gold in grams?

A. none of these

B. 6.5 × 101 g

C. 1.8 × 102 g

D. 1.28 × 102 g

E. 1.08 × 102 g

Answer 1

1) answer : B) 35.1

mass = 10.0 mg

molar mass = 16 x 12 + 13 x 1 + 2 x 14 + 16 + 35.5 = 284.5 g/mol

moles = mass / molar mass

          = 10 x 10^3 / 284.5

moles = 35.1 mol

2) answer : C) 3.61 x 10^24

AgNO3

1 mol AgNO3 -------------> 3 x 6.023 x 10^23 Oxygen atoms

2 mol AgNO3   -------------->   ??

moles of Oxygen atoms = 2 x 3 x 6.023 x 10^23

                                     = 3.61 x 10^24 atoms

3)

C) . 1.00 mole of CH3CO2H.