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Calculate the percentage by mass of nitrogen in an ammonia molecule (NH​​​​​​​3) . Take the relative atomic masses of hydrogen and nitrogen to be 1 and 14 respectively.

Calculating the mass of 1 molecule of ammonia: Mass = ( Number of hydrogen atoms x Mass of hydrogen atom) + ( Number of nitrogen atoms x Mass of nitrogen atoms) Mass = ( 3 x 1 ) + ( 1 x 14) = 17 Calculating ...
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Answered by Nic D. • Chemistry tutor
30124 Views

Explain one consequence of a more globalised world?

More interdependency More free trade Increased competition
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Answered by Saqlain C. • Economics tutor
2376 Views

How do you know when to use sin, cos and tan?

First draw the triangle and label all the information you have as well as the unknown angle or side length. There should be at least one angle labelled with some informtion - use this angle to label the oppo...
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Answered by Anna W. • Maths tutor
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Why do cells have receptors that allow viruses to invade?

Rather than cells having receptors specific to viruses, cells have receptors specific to molecules it needs to acquire from outside the cell, such as glucose (needed for respiration). It is the viruses who a...
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Answered by Emily R. • Biology tutor
5001 Views

How do I analyse art?

When analysing art, you should first of all find out when the piece was created, who created it and what the piece was created using (for example, is it a painting? a sculpture or a photo?). After you have f...
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Answered by James S. • Art tutor
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