midterm

Select largest mass from the following values:

• 1.25×10^6 μg

• 1.25×10^-3 kg

• 1.25×10^4 mg

• 1.25×10^2 cg

What is the volume of 5.25 g of Osmium? The density of Osmium is 22.6 g/mL

• 1.19 mL

• 0.561 mL

• 3.430 mL

• 0.232 mL

The melting point of mercury is – 39 °C. What is the value in Kelvin?

• 298 K

• 273 K

• 312 K

• 234 K

Find the number of significant figures in 9.09090

• 5

• 4

• 3

• 2

Round off the following number to three significant figures: 0.009046879855

• 0.0090469

• 0.00904

• 0.009047

• 0.00905

Calculate and give the answer with the correct number of significant figure: (3.4+100.33)/2.4 =

• 43

• 40

• 43.21

• 43.2

How many ions Li+ are contained in 0.856 g Li2O?

• 1.73×10^23 ions Li+

• 6.90×10^24 ions Li+

• 1.73×10^22 ions Li+

• 3.45×10^22 ions Li+

Complete the following sentence: 'The isotopes of the same element are atoms having...'

• The same number of protons and neutrons, but different numbers of electrons

• The same number of protons, but different numbers of neutrons and electrons

• The same number of neutrons, but different numbers of protons and electrons

• The same number of protons and electrons, but different numbers of neutrons

Consider the following atoms: 76Ga, 78As and 80Br. These atoms have:

• The same mass number.

• The same number of electrons.

• The same number of protons.

• The same number of neutrons.

The name of SnS2 is (Sn is a metal):

• Tin(IV) disulfide

• Tin(II) sulfide

• Tin disulfide

• Tin sulfide