Cadmium was discovered and isolated by two German chemists Karl Samuel Leberecht Hermann and Friedrich Stromeyer in 1817.

## Which element has a larger atomic radius than sulfur? Chlorine, cadmium, fluorine or oxygen?

The atomic radii computed from theoretical models was published by Enrico Clementi and others in 1967.

The atomic radius of sulfur = 88 pm.

The atomic radius of Chlorine = 79 pm.

The atomic radius of Cadmium = 161 pm

The atomic radius of fluorine = 42 pm

The atomic radius of oxygen = 48 pm

pm =  picometers ( 1×10−12 m)

## Where is cadmium found?

Cadmium is found in ore like greenockite. Cadmium is produced as a by-product of mining. It is collected and refined from Zinc and sulfidic ores. Rocks mined for phosphate fertilizer also contain a small amount of cadmium. China is the top producer of Cadmium followed by South Korea and Japan.

## What is the number of valence electrons in cadmium (cd)?

Cadmium has two valence electrons. Its electronic configuration is 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10, 4p6, 4d10, and 5s2. ([Kr] 4d10 5s2). There are 48 electrons, 48 protons and 64 neutrons.

## If a sample of pure cadmium has a mass of 18.2 grams, how many moles of cadmium are in the sample?

Given data;

mass of substance = 18.2 grams.

Required data:

find the number of moles =?

Formula:

moles = mass ÷ molar mass.

As we know the molar mass of cadmium is 112.41 gram/mol.

Now put the values in the above formula.

Moles = 18.2 g ÷ 112.41g/mol = 0.161 mol.

No of moles of cadmium = 0.161 mol.