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What are the oxidation numbers of each element in these examples: a) H2SO4 b) N2 c) NH4+

a) H₂SO₄ANSWER: H: +1 S: +6 O: -2 b) N₂ANSWER: N: 0 (all elements not within a compound have an oxidation number of 0 eg I₂, O₂, K) c) NH₄

Answered by Georgia B. • Chemistry tutor

2649 Views

Explore the presentation and perception of unconventional love in three texts

The easiest ways to distinguish yourself with these sorts of questions is to keep your approach entirely thematic, avoiding any sense of chronology or order. It's all too easy to slip into analysing a tex...

Answered by Hudson G. • English Literature tutor

3734 Views

What is meant by a monopoly?

The legal definition of a monopoly is, any firm within an industry which possesses more than 25% market share. This can give an insight into how a 'monopoly' firm behaves, compared to firms in other forms...

Answered by Tutor72196 D. • Economics tutor

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A school has 1200 pupils. 575 of these pupils are girls. 2/5 of the girls like sports. 3/5 of the boys like sport. Work out the total number of pupils in the school who like sport.

As we are told the number of girls that are in the school, our first step should be to calculate the number of boys in the school through a simple subtraction (1200-575 = 625). After this we are told that...

Answered by Gianluca B. • Maths tutor

13687 Views

A radio sells for £63, after a 40% increase in the cost price. Find the cost price.

X+2/5X = 63 or 63 = 140%

First we need to understand that the original price (X) has been increased by 40%. Hence, by 2/5 (40/100 = 40%) of its original value, in other words, 2/5X.

To find ...

Answered by Gianluca B. • Maths tutor

6288 Views