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How to predict the bond angle and shape of a molecule of NH3

An atom of nitrogen has 5 valence electrons in its outer shell. Each hydrogen atom in ammonia bonds to the central nitrogen atom and contributes an electron each. This means there are 8 electrons in total...

Answered by Daidria P. • Chemistry tutor

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Why does a higher temperature means the rate of reaction is faster?

As you increase the temperature of a system, the particles gain more kinetic energy and move about more. This means that particles are likely to collide more frequently. These collisions are also likely t...

Answered by Daidria P. • Chemistry tutor

1729 Views

Back in 1950s, it was common to have as house cleaning items bleaching solution (containing sodium hypochlorite) and ammonia (used to remove, for example, hair dye stains). However, many people ended up in hospital after using them both, why?

Hypochlorite reacts with ammonia to yield chloramine and water. (emphasise to the students that hypochlorite is an oxidising agent, getting reduced to chloride ions). chloramine is a very toxic gas, since...

Answered by Radu B. • Chemistry tutor

2594 Views

Calculate the relative atomic mass of an atom.

You will need to multiply the mass of each isotope (the same atom with a different mass number) by the percentage abundance of that isotope. Then, add all these values together and divide by 100. This wil...

Answered by Emily D. • Chemistry tutor

1539 Views

A solution of sugar has a concentration of 3 g/dm3. What is the mass of sugar in 0.5 dm3 of solution?

The key to this question is understanding the relationship between concentration, mass and volume. Concentration shows how much of a substance (the mass) is packed into a space (the volume). This means th...

Answered by Daniel D. • Chemistry tutor

7274 Views