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Chemistry

A Level

electron arrangement in atoms

Work out what they know

how are shells arranged?

how do electrons arrange themselves within the shells?

how many electrons per shell?

types of shells

how to write the a...

Answered by Lucy N. • Chemistry tutor

1774 Views

Calculate the mass of sodium amide needed to obtain 550 g of sodium azide, assuming there is a 95.0% yield of sodium azide. Give your answer to 3 significant figures.

2NaNH2 + N2O --> NaN3 + NaOH + NH3

Mr(NaN3) = 65 Mr(NaNH2) = 39
n(NaN3) = 550/65 = 8.46
100% NaN3 = 550/65 x 100/95 = 8.91
n(NaNH2) = 2 x 8.91 = 17.8
m(NaNH2) = 17....

Answered by Kathleen M. • Chemistry tutor

13592 Views

Determine whether a tertiary halogenoalkane will undergo a SN1 or SN2 reaction. Explain your choice.

Tertiary halogenoalkanes will undergo a SN1 reaction. This means that there is 1 molecule in the rate determining step, which is the slowest step. Because of the bulky alkyl groups surrounding the central...

Answered by Ganesh V. • Chemistry tutor

15933 Views

When testing for primary, secondary, and teritary alcohols what is the testing reagent and the results of the test?

Testing reagent= Acidified solution of potassium dichromate (VI). The alcohol is added and the mixture is heated.

For a primary alcohol- the mixture changes from orange (Cr2O72-) to green (Cr...

Answered by Anna G. • Chemistry tutor

20043 Views

How can you tell what shape a molecule is going to be?

The key to determining the shapes of molecules is to think about number of lone and bonded pairs of elections and the interactions between these pairs. In doing this we apply the valence-shell election-pa...

Answered by Anna M. • Chemistry tutor

1709 Views