use the chemical equations for the complete combustion and incomplete combustion of propane to show that matter is conserved in both situations

Explanation:

1) Complete combustion of propane gives carbon dioxide gas and water vapors.

The balanced chemical equation is given as:

Number of carbon atoms on reactant side = 3

Number of hydrogen atoms on reactant side = 8

Number of oxygen atoms on reactant side = 10

Number of carbon atoms on the product side = 3

Number of hydrogen atoms on the product side = 8

Number of oxygen atoms on the product side = 10

On both the sides numbers, all elements remained the same which indicates that matter remains conserved during the course of a chemical reaction.

2) Incomplete combustion of propane gives carbon dioxide gas, carbon monoxide gas, and water vapors.

The balanced chemical equation is given as:

Number of carbon atoms on reactant side = 6

Number of hydrogen atoms on reactant side = 16

Number of oxygen atoms on reactant side = 18

Number of carbon atoms on the product side = 6

Number of hydrogen atoms on the product side = 16

Number of oxygen atoms on the product side = 18

On both the sides numbers, all elements remained the same which indicates that matter remains conserved during the course of a chemical reaction.

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error