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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

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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

4880 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

3640 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

13465 Views

Polyester is a common polymer used in clothing. State the name of the chemical reaction used to form polyester by reaction of ethanedioic acid and ethane-1,2-diol. Give the name of the molecule which is lost upon condensation of these two molecules.

Name of reaction is condensation polymerisation.Water is lost upon condensation of ethanedioic acid and ethane-1,2-diol (will draw this out on the whiteboard).

Answered by Melissa W. • Chemistry tutor

2906 Views