Answer:
The number of protons is equal to the mass number of the element. Since an element always has a different number of protons, the mass can indicate how many neutrons are in an isotope. Atoms of the same element can have a different number of neutrons. There are three naturally-occurring isotopes of carbon.
Explanation:
The weathering process caused by cycles of freezing and thawing of water in surface pores, cracks, and other openings
They depend on nitrogen-fixing bacteria, which convert atmospheric nitrogen into a usable form.
Molar mass NO₂ = 46.0 g/mol
1 mole -------- 46.0 g
2.0 moles ----- ?
Mass (NO₂) = 2.0 x 46.0 / 1
=> 92.0 g
hope this helps!
Answer: a) 
acid : hydronium ion
base : methoxide ion
conjugate acid : methanol
conjugate base: water
b) 
acid : hydrogen chloride
base : ethoxide ion
conjugate acid : ethanol
conjugate base: chloride ion
c) 
acid : methanol
base : amide ion
conjugate acid : ammonia
conjugate base: methoxide ion
Explanation:
According to the Bronsted-Lowry conjugate acid-base theory, an acid is defined as a substance which looses donates protons and thus forming conjugate base and a base is defined as a substance which accepts protons and thus forming conjugate acid.
The species accepting a proton is considered as a base and after accepting a proton, it forms a conjugate acid.
The species losing a proton is considered as an acid and after loosing a proton, it forms a conjugate base
For the given chemical equation:
a) 
acid : hydronium ion
base : methoxide ion
conjugate acid : methanol
conjugate base: water
b) 
acid : hydrogen chloride
base : ethoxide ion
conjugate acid : ethanol
conjugate base: chloride ion
c) 
acid : methanol
base : amide ion
conjugate acid : ammonia
conjugate base: methoxide ion
.