Moles Atoms Electrons

The number of atoms in 0.1 mole of a triatomic gas is (N_A= 6.02 x 10²³ mol^-1):

1. $6.026\backslash times{10}^{22}$

2. $1.806\backslash times{10}^{23}$

3. $3.600\backslash times{10}^{23}$

4. $1.800\backslash times{10}^{22}$

If Avogadro number , is changed from$\mathrm{}$ to this would change the:

1.	Definition of mass in units of grams
2.	Mass of one mole of carbon
3.	Coefficient of chemical species in a balanced equation
4.	Ratio of elements in a compound

The number of water molecules are maximum in:

1. 18 molecules of water
2. 1.8 g of water
3. 18 g of water
4. 18 moles of water

The maximum number of water molecules among the following is:

1. 18 mL of water
2. 0.18 g of water
3. 0.00224 L water vapours at 1 atm and 273 K
4. 10^-3 mol of water

One mole of carbon atoms has a mass of 12 g. Determine the number of atoms present in this sample:
(Given: Mass of is $1.9926\backslash times{10}^{-23}$ $g$)

1.	$1.2\backslash times{10}^{23}$	2.	$6.022\backslash times{10}^{22}$
3.	$12\backslash times{10}^{22}$	4.	$6.022\backslash times{10}^{23}$

Which of the following contains the highest number of helium atoms?

1. 4 u of helium
2. 4 g of helium
3. 2.27 L of helium at STP
4. 4 mol of helium

Consider the following data of compounds:

A.
B.
C.
D.
E.

Which of the following represents a correct set of compounds having an equal number of atoms?
1. B, C, and D only
2. B, D, and E only
3. A, B, and C only
4. A, B, and D only