How many moles are in 128.9 grams of Cr2(SO3)2?

0.5 moles

Explanation:

Cr2(SO3)2 is the chemical formula for chromium sulphate.

Given that,

Amount of moles of Cr2(SO3)2 (n) = ?

Mass of Cr2(SO3)2 in grams = 128.9g

For molar mass of Cr2(SO3)2, use the atomic masses:

Chromium, Cr = 52g;

Sulphur, S = 32g;

Oxygen, O = 16g

Cr2(SO3)2 =

(52g x 2) + [(32g + 16g x 3) x 2]

= 104g + [(32g + 48g) x 2]

= 104g + [80g x 2]

= 104g + 160g

= 264g/mol

Since, n = mass in grams / molar mass

n = 128.9g / 264g/mol

n = 0.488 mole [Round the value of n to the nearest tenth which is 0.5

Thus, there are 0.5 moles in 128.9 grams of Cr2(SO3)2

the cold front replaces the warmer air at the ground level changing the wind to be breezy and denser.there is also an immediate drop in the temperature.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8