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What is the test for CO2 gas? Describe the overall reaction that takes place in the instance of a positive result and write its reaction equation.

The gas is passed through a container of Lime-water, if the Lime-water goes cloudy it means that the gas is CO2. The Carbon dioxide reacts with Calcium hydroxide to produce a Calcium carbonate precipitate...

Answered by Aarran O. • Chemistry tutor

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What is the difference between oxidation and reduction?

Oxidation and reduction are considered opposites in terms of electrons moving. Oxidation occurs when an electron is lost, while reduction occurs when an electron is gained. It is often seen with oxygen be...

Answered by Luke P. • Chemistry tutor

1942 Views

How do I balance C4H8 + O2 --> CO2 + H2O?

When balancing a reaction, you first want to count how many particles there are of each element on each side.You then want to try and make both sides the same for each element. In this case we're going to...

Answered by Aiman K. • Chemistry tutor

5643 Views

Calculate the number of moles of carbon dioxide molecules in 11 g of CO2.

Use equation: mole=mass/mr Calculate Mr of CO2 = 44Moles= 11g/44= 0.25 moles

Answered by Mujahid R. • Chemistry tutor

4433 Views

The enthalpy of combustion of ethanol is −1371 kJ mol−1 . The density of ethanol is 0.789 g cm−3 . Calculate the heat energy released in kJ when 1 dm3 of ethanol is burned.

1 dm3 of ethanol is equal to 1000 cm3, so the mass of ethanol used is =density x volume = 0.789 g cm-3 x 1000 cm3 = 789gMolar mass of ethanol = (2x12)+(6x1) +(1x16)= 46 g mol-1Moles of ethanol = mass/mola...

Answered by Sophie L. • Chemistry tutor

14878 Views