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A compound is found to contain 37.21% carbon, 7.75% hydrogen and 55.04% chlorine. What is it's empirical formula?

Carbon: 37.21/12= 3.1Hydrogen:7.75/1=7.75Chlorine: 55.04/35.5=1.55Ratio:c:H:Cl3.1:7.75:1.552:5:1Therefore empirical formula= C₂H₅Cl

Answered by Lucy P. • Chemistry tutor

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Expand the following expression and simplify: (3x+2)(4x+5)

12x² + 15x + 8x + 10 = 12x² + 23x + 10

Answered by Priscilla D. • Maths tutor

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A car depreciates at 8% per year. The initial price of the car is £25,000. How much will the car be worth after 4 years? After how many years will the car be worth less than £14,000?

This problem is all about compound interest except this time the value is going down not up. To increase a value by 8% you would multiply it by 1.08 as 8% is 0.08 (1+0.08). To decrease a value however you...

Answered by Hannah T. • Maths tutor

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The formula v = u +at gives the final velocity of an object as it accelerates. If v= 35, a=4 and t=5 then find u

First off, you would start by substituting in the numbers that you already know.
Therefore you get: 35 = u + (4 x 5)
Remembering BODMAS you would then look at the equation and solve the bracket...

Answered by Hannah G. • Maths tutor

9979 Views

How do you determine the shape and bond angle of an ammonia molecule?

Firstly, how many electrons does nitrogen have in its outer shell?... Nitrogen is in group 5, so 5.How many more electrons does nitrogen need to give it a full outer shell?... 8 electrons provide a full o...

Answered by • Chemistry tutor

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