Water is a pure substance because it is not refined like the other materials. Hope this helps!!!
Explanation:
If there are two bond pairs and two lone pairs of electrons the molecular geometry is angular or bent (e.g. H2O). Five electron pairs give a starting point that is a trigonal bipyramidal structure.
Let's say say there are n1 mols of helium in the first balloon and n2 mols of nitrogen in the second one, which are equivalent to m1 grams of helium and m2 grams of nitrogen.
The molar mass of hydrogen is thus M1=m1/n1, same for nitrogen M2=m2/n2 hence the ratio of their masses is m1/m2=(M1n1)/(M2n2). Since both gases are rather similar, we can assume that n1~n2 hence m1/m2=M1/M2
Some Gases are lighter than air
Remember,Air is a mixture of gases
So you cant tell!
It depends on the gas
Hope i helped
Answer:
The answer is
D. Main sequence
Explanation:
Main sequence stars can be between one thousand times dimmer and one million times brighter than the Sun.
What is main sequence stars?
A main sequence star is any star that is fusing hydrogen in its core and has a stable balance of outward pressure from core nuclear fusion and gravitational forces pushing inward.
