Answer:
It’s true
Explanation:
If we account for all reactants and products in a chemical reaction, the total mass will be the same at any point in time in any closed system. ... The Law of Conservation of Mass holds true because naturally occurring elements are very stable at the conditions found on the surface of the Earth.
Using ideal gas equation,

Here,
P denotes pressure
V denotes volume
n denotes number of moles of gas
R denotes gas constant
T denotes temperature
The values at STP will be:
P=1 atm
T=25 C+273 K =298.15K
V=663 ml=0.663L
R=0.0821 atm L mol ⁻¹
Mass of gas given=1.25 g g
Molar mass of gas given=?


Putting all the values in the above equation,

Molar mass of the gas=46.15
1. cooking
2. cleaning
3.you use chemistry in science class (a.k.a. science experiments)
4. at your job depending on were you work
Answer:
B
Explanation:
the energy of two separate hydrogen atoms decreases as they approach each other, and the single electrons on each atom are shared to form a covalent bond.
For the first one, you have to find one that has both a metal and a nonmetal in it, plus potassium. Bonds between nonmetals are called covalent because they share electrons and a bond between a metal and a nonmetal is an ionic bond because they exchange electrons.
Potassium chloride is KCl. Only an ionic bond.
Potassium hydride is KH. Only an ionic bond.
Potassium nitrate is KNO3. There we go, that has a covalent bond between the nitrogen and oxygen, and an ionic bond between potassium and the nitrogen and oxygen.
For the second one, potassium chloride is the answer because the other three also have covalent bonds. Chloride is the only one that isn't a compound.