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CHEMISTRY, M2 EQ-Bank 3 MC

The following equation represents the reaction of calcium disilicide with antimony trichloride to produce calcium chloride , silicon , and antimony :

What are the stoichiometric values for and  in the balanced equation?

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→ Balancing the chlorine atoms: 

→ Since and are by themselves on the right hand side, they can be easily balanced last.

→ Next, balance the atoms on the left hand side:

→ The values for and can be added to balance the remaining atoms.

CHEMISTRY, M2 EQ-Bank 1 MC

What numbers are required to correctly balance this equation?

__ __ __ __

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Balancing the iron atoms:

→ There are 2 Fe atoms in , so we place a 2 in front of  on the product side.


 

Balancing the oxygen atoms:

→ has 3 oxygen atoms. To balance equation, we need 3 molecules on the reactant side to balance the 3 molecules on the product side.

CHEMISTRY, M2 2013 VCE 8a

In an experiment, 5.85 g of ethanol was ignited with 14.2 g of oxygen.

  1. Write an equation for the complete combustion of ethanol.  (1 mark)

  2. Which reagent is in excess? Calculate the amount, in moles, of the reagent identified as being in excess.  (3 marks)

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♦ Mean mark 43%.

 
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CHEMISTRY, M2 2014 VCE 11*

Consider the following unbalanced ionic equation.

When this equation is completely balanced including the total charge on each side of the equation, find the coefficient of .   (3 marks)

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→ By balancing the equations by the total number of atoms of each side

→ The charge on the left side is while the charge on the right side is

→ The charge on the right hand side needs to be increased by

→ This can be done by changing to .

→ The total balanced equation while following law of conservation of charge is:

→ Hence the coefficient of is .

CHEMISTRY, M2 2020 VCE 6a*

Methane gas, , can be captured from the breakdown of waste in landfills. is also a primary component of natural gas. can be used to produce energy through combustion.

Write the balanced equation for the complete combustion of to produce carbon dioxide, given the unbalanced equation below.  (1 mark)

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CHEMISTRY, M2 2016 VCE 9a

Standard solutions of sodium hydroxide, , must be kept in airtight containers. This is because is a strong base and absorbs acidic oxides, such as carbon dioxide, , from the air and reacts with them. As a result, the concentration of is changed to an unknown extent.

in the air reacts with water to form carbonic acid, . This can react with to form sodium carbonate, .

  1. Write a balanced overall equation for the reaction between gas and water to form .   (1 mark)

  2. Write a balanced equation for the complete reaction between and to form .   (1 mark)

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CHEMISTRY, M2 2010 HSC 23a

  1. Write a balanced chemical equation for the complete combustion of 1-butanol.  (1 mark)
  2. A student measured the heat of combustion of three different fuels. The results are shown in the table.

  1. The published value for the heat of combustion of 1-butanol is 2676 kJ mol.
  2. Which fuel from the table is likely to be 1-butanol? Justify your answer.  (2 marks)

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CHEMISTRY, M2 2013 HSC 22b

A solution contains three cations, and . The flow chart indicates the plan used to confirm the identity of these cations.
 

 

Write a balanced net ionic equation for the formation of Precipitate 1.  (2 marks)

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→ In the above flow chart, the addition of excess HCl causes one of the cations to precipitate out of the solution.

→ The remaining two are then distinguished through precipitation with excess sulfuric acid .

→ Of the possible salts, only is insoluble. Therefore Precipitate 1 is Lead Chloride.

→ Balanced net ionic equation: 

♦♦♦ Mean mark 27%.