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The halogens are elements in Group 7. Bromide is in Group 7. How many electrons are there in the outer shell of a bromine atom? (1 mark)

7 electrons.

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Solve these simultaneous equations (1) 12x + 3.5y = 32 (2) 8x + 3y = 24

Make the like terms equate by multiplying (1)*2 and (2)*3, ((1)*2) 24x+7y=64, ((2)*3) 24x+9y=72, Take one away from the other to remove the x term and solve for y, (24x+9y=72) - (24x+7y=64), 2y=8 y=4, Su...

Answered by Karen J. • Maths tutor

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Using collision theory, explain why increasing the concentration of a reactant increases the rate of reaction.

Chemical reactions occur when reacting particles collide with energy equal to or greater than the activation energy. By increasing the concentration of reactants, there are more reacting particl...

Answered by Alexandra H. • Chemistry tutor

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Describe the process of diffusion with an example.

Diffusion is the moving of solutes from a region of higher solute concentration to a region of low solute concentration. It does not require energy so we say it is a “passive process” and it can occur it ...

Answered by Emmanouella X. • Biology tutor

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What will be the resulting molecule if carbon-14 underwent beta decay?

For beta decay, the atomic mass (top number) stays the same and the atomic number (bottom number) increases by one.This will give a nitrogen molecule and beta particle.

Answered by Caitlin W. • Chemistry tutor

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