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How do I do redox calculations?

For example,Iron(II) sulphate can be oxidised using acidified potassium permanganate solution. Calculate the mass of iron(II) sulphate which will completely react with 200 cm3 of 0.25 mol l-1 acidified perma...
CG
3157 Views

Rewrite (2+(12)^(1/2))/(2+3^(1/2)) in the form a+b((c)^(1/2))

To solve:Rewrite the top part of the fraction to get it in terms of 3^(1/2)Rationalise the denominatorSimplify The final answer is 2(3^(1/2)) - 2
MM
Answered by Max M. • Maths tutor
4086 Views

You're on a game show and have a choice of three boxes, in one box is £10, 000 in the other two are nothing. You pick one box, the host then opens one of the other boxes showing it's empty, should you stick or switch?

At the moment of your first choice you have a 1/3 chance of picking the box with the prize and a 2/3 chance of getting nothing. After your choice those probabilities remain locked in and do not change as whe...
JB
Answered by Jonathan B. • Maths tutor
9339 Views

You are sitting in a boat on a lake, you have with you in the boat a large rock. You throw the rock out of the boat and it sinks to the bottom of the lake, does the water level of the lake go up, down or stay the same?

Whilst in the boat the rock (and you) are floating, this means that the amount of water displaced by the rock is the mass of the rock. When the rock sinks to the bottom of the lake the amount of water displa...
JB
Answered by Jonathan B. • Physics tutor
10905 Views

How is the factor theorem used?

The factor theorem is used to determine factors of large polynomials so that we can split large polynomials into a product of linear polynomials. Say we have a cubic polynomial of the form f(x)=x^3+bx^2+cx+d...
RD
Answered by Rob D. • Maths tutor
4120 Views