Diamonds and graphite are both made of carbon
I tried to answer this but forgot answer gg
Answer : The correct option is, (A) the copper must have combined with another substance.
Explanation :
According to the question, when a sample of copper powder is heated in an evaporating dish by using Bunsen burner then the mass of the powder in the evaporating dish increases after heating that means the copper powder will be combined with the another substance.
If the mass of powder in the evaporating dish is decreases after the heating then the copper powder must have lost some matter.
The given option C and D are wrong statements because the hot copper is less dense than the cold copper and as we know that the density is directly proportional to the mass of a substance that means the hot copper weighs less than cold copper.
Hence, the correct option is, (A) the copper must have combined with another substance.
Answer:
496 g of Fe₂O₃.
Explanation:
The balanced equation for the reaction is given below:
4Fe + 3O₂ —> 2Fe₂O₃
From the balanced equation above,
4 moles of Fe reacted to produce 2 moles of Fe₂O₃.
Therefore, 6.20 moles of Fe will react to produce = (6.20 × 2)/4 = 3.1 moles of Fe₂O₃
Finally, we shall determine the mass of 3.1 moles of Fe₂O₃. This can be obtained as follow:
Mole of Fe₂O₃ = 3.1 moles
Molar mass of Fe₂O₃ = (56 × 2) + (3×16)
= 112 + 48
= 160 g/mol
Mass of Fe₂O₃ =?
Mass = mole × molar mass
Mass of Fe₂O₃ = 3.1 × 160
Mass of Fe₂O₃ = 496 g
Therefore, 496 g of Fe₂O₃ were produced from the reaction.
Answer:
Option b. The entire container because gases will expand to fill it.
Explanation:
One exceptional ability of gas is to fill the container in which they are poured into. Since the forces of cohesion within the gas molecules are negligible, the gases will expand to fill the entire container