Vanadium has an atomic mass of 50.9415 amu. it has two common isotopes. one isotopes has a mass of 50.9440 amu and a relative abundance of 99.75% .

Isotope simply means one of the forms of a chemical element. The mass of the second isotope of vanadium is 49.944 amu

Given that:

--- atomic mass of vanadium

---- the mass of the first isotope

---- the relative abundance of the first isotope

The following equation can be used to calculate the mass of the second isotope.

Where:

So, we have:

Collect like terms

Solve for

Hence, the mass of the second isotope is 49.944 amu

Read more about isotopes at:

link

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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