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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

3068 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

19234 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

2226 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

9411 Views

When a new antigen is presented to the immune system, an immune response leads to antibodies are released. The second time this happens it is much faster - explain why

In the primary immune response, there is antigen presentation followed by clonal selection, expansion and differentiation of helper t cells. This leads to plasma cells releasing antibodies and the develop...

Answered by Maxine R. • Biology tutor

2791 Views