Answer:
B. Atoms in the original substances are arranged in a different way to make new substances.
Explanation:
The best statement that describes a change that occurs in a chemical reaction is that atoms in the original substances are arranged in a different way to make new substances.
- Chemical reactions obey the law of conservation of matter.
- The law postulates that "matter is neither created nor destroyed in a chemical reaction but they are simply rearranged".
- Therefore, atoms of compounds forms new bonds by rearranging to give a new product.
2.41 molecules, should be it
Answer:
Explanation:
= Initial pressure = 931 torr = 
= Final pressure = 113 kPa
= Initial volume = 350 mL
= Final volume
From the Boyle's law we have
The volume the gas would occupy is .
Answer:
Y, Q, W, Z and X
Y > Q > W > Z > X
Explanation:
To know the most reactive element, the element will be able to displace other metal in it compound. We also have to observe if the reaction occur. If the reaction didn't occur, that means the element is not reactive than the metal found in the other reactant. Invariably their will be no displacement.
Q + w+ Reaction occurs
Q element displace the metal w in it compound . This means Q is more reactive.
x +z+ No reaction
No reaction here. This means x is less reactive than z as it couldn't displace z in it compound.
w + z+ Reaction occurs
w is more reactive than z as it displaces z in it compound.
Q+ + Y Reaction occurs
Y is more reactive than Q as it displaces Q in it compounds.
Therefore, the most reactive to the least reactive is arrange as follows.
Y, Q, W, Z and X
