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Ammonia is made from nitrogen and hydrogen in a reversible reaction. Write a balanced symbol equation for this reaction, name the reaction and give one use for ammonia.

N₂ + 3H₂⇌ 2NH₃The Haber process, and ammonia is used in the production of many synthetic fertilizers.

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A gene often has two alleles. One allele is dominant and the other allele is recessive. When is a recessive allele expressed as a characteristic?

A gene has two alleles, they can be either dominant (A) or recessive (a).So the possible combinations are:AAAaaaDominant alleles are expressed as they are 'stronger' . So in the Aa example the dominant al...

Answered by Thomas G. • Biology tutor

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When do we add and when do we multiply probabilities?

We add probabilities when the corresponding events are alternatives, e.g. P(rolling a 4 on a pair of dice) = P(rolling a 1 and a 3) + P(rolling a 2 and a 2). These are mutually exclusive events which can'...

Answered by Liora W. • Maths tutor

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What is meant by the different sectors of economies?

Economies are made up of three sectors; the primary sector, which involves extraction of raw materials (e.g. timber), the secondary sector, which is concerned with manufacturing (e.g. turning timber into ...

Answered by Liora W. • Economics tutor

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What are the properties of electromagnetic waves?

EM waves invariantly travel at the speed of light, and can do so in a vacuum. They transfer energy from their source to the absorber. Some kinds of EM waves can be reflected and refracted. The spectrum of...

Answered by Liora W. • Physics tutor

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