Search our library of Chemistry questions

Top answers

Chemistry

All levels

A student wanted to make 10.0 g of zinc chloride. The equation for the reaction is: ZnO(aq) + 2HCl(aq) → ZnCl2(aq) + H2O(l) Calculate the mass of zinc oxide the student needs to react with the dilute acid to make 10.0 g of zinc chloride. [4 marks]

What do we know from the question? 1. we know the balanced equation 2. we know the mass of zinc chloride we want to form. using the equation number of moles = mass/Mr we can calculate the number of moles ...

Answered by Arun S. • Chemistry tutor

6499 Views

How many molecules of water are present in 5g sample?

In order to measure the amount of water molecules, we need to use following equation:
n = m / M where n is the amount of water molecules in molesm is the mass in grammesM is the molecular mass of wat...

Answered by • Chemistry tutor

16712 Views

Explain the bonding in and the shape of a benzene molecule.

Stage 1 -Bonding 1a) Each C has three (covalent) bonds 1b) Spare electrons (in a p orbital) overlap (to form a pi cloud) 1c) delocalisation
Stage 2 -Shape 2a) Planar 2b) Hexagon/6 carbon ring/120o b...

Answered by Yousif C. • Chemistry tutor

2248 Views

Potassium forms an ionic compound with sulfur. Describe what happens when two atoms of potassium reaction with one atom of sulfur (5 marks)

In this question we need to give our answer in terms of electron transfer: Electrons are transferred from potassium to sulfur. Two potassium atoms each lose one electron forming K⁺ ions. Sulfur...

Answered by Megan L. • Chemistry tutor

2310 Views