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Solve the simultaneous equations 3x + 2y = 4, 4x + 5y = 17

To solve this pair of simultaneous equation I will use the substitution method however the elimination method could also be used here.
Eq1. 3x + 2y = 4
Eq2. 4x + 5y = 17
First rearrange Eq1...

Answered by George H. • Maths tutor

4568 Views

Propane burns completely to produce carbon dioxide and water. Describe how you would use limewater to show that carbon dioxide is produced.

If carbon dioxide is present, when the solution produced is mixed with lime water if it turns cloudy this will prove that carbon dioxide is present.

Answered by Huzair A. • Chemistry tutor

2839 Views

Predict whether the lattice energy of magnesium oxide, MgO, is more or less exothermic than the lattice energy of magnesium sulfide, MgS. Justify your answer in terms of the sizes and the charges of the ions involved.

To start with, we can clearly see that the difference between MgO and MgS is the anions, we have O(2-) and S(2-). As we know (from looking at the periodic table) O(2-) has a smaller ionic radius, and ther...

Answered by Huzair A. • Chemistry tutor

18177 Views

When should I use "qui" and when should I use "que"?

A relative pronoun, such as “qui” or “que”, is a word that is used to connect two parts of a sentence together when referring to someone or something that has already been mentioned earl...

Answered by William O. • French tutor

1979 Views

Define a hydrocarbon and explain the difference between alkenes and alkanes.

A Hydrocarbon is an organic molecule containing only hydrogen and carbon atoms. Alkanes are saturated hydrocarbons, meaning they are only made up of single bonds. The carbons are 'saturated' with hydrogen...

Answered by Saskia H. • Chemistry tutor

8465 Views