75% hydrogen
25% helium
2%carbon, nitrogen
Answer:The world population increased from 1 billion in 1800 to 7.7 billion today. The world population growth rate declined from 2.2% per year 50 years ago to 1.05% per year. Other relevant research: World population growth – This article is focusing on the history of population growth up to the present.
Explanation:
2ZnS(s)+3O2(g) -> 2Zns(s) + 2SO3(g)
the above given equation is unbalanced as it contains 4 moles of sulphur in the output but in the input there are only two aoms of sulphur so to balance the equation we will write the equation as given under
balanced equation is
2ZnS(s)+3O2(g) -> 2Zn(s) + 2SO3(g)
In words:
When 2 moles of solid zinc sulfide reacts with 3 moles of oxygen gas gives 2 moles of solid zinc and 2 moles of sulphur trioxide gas.
C Size
A change of size in any object is a physical change. So, a specific type of physical change is a SIZE change.