Answer:
Rock
Explanation:
Let's calculate the density of each object:
Rock:
Pencil:

Therefore the rock is denser.
Answer:
2.03 moles of Gold
Explanation:
Gold is one of the most precious metal metal used in many applications and mainly as a jewellery. In terms of purity it is categorized in Karats. 24 Karat is considered the purest Gold (i.e. 100 % Gold) while other Karats (14, 18, 22 e.t.c) are alloys with other metals and gyms.
Data Given:
Mass of Gold = 400 g
A.Mass of Gold = 196.97 g.mol⁻¹
Calculate Moles of Gold as,
Moles = Mass ÷ M.Mass
Putting values,
Moles = 400 g ÷ 196.97 g.mol⁻¹
Moles = 2.03 moles of Gold
6g of hydrogen gas is my answer. I'm sorry if I'm wrong.
Answer:
The yeast present contains an enzyme called catalase which catalyses the reaction. More the amount of the catalyst added, faster will be the decomposition of the hydrogen peroxide.