Answer:
Hello!!! Princess Sakura here ^^
Explanation:
They are called isotopes.
I’m pretty sure it’s abode and cathode
A match-head is flammable, but you have to get it up to its ignition temperature first.
A diamond is flammable, but its ignition temperature is astronomical and
totally out of sight.
Answer: The de broglie wavelength is
.
Explanation:
Calculate
as follows.

where,
h = plank's constant = 
p = momentum = 
Putting the values in the formula as follows.

=
= 
Thus, the de broglie wavelength is
.
I’m assuming you mean barium nitrite, Ba(NO2)2.
First convert grams of Ba(NO2)2 to moles using the molar mass of Ba(NO2)2. Then use the mole ratio of 4 moles of oxygen per 1 mole of Ba(NO2)2 to convert to moles of oxygen. Then use the molar mass of oxygen to convert to grams of oxygen.
45.7 g Ba(NO2)2 • 1 mol Ba(NO2)2 / 229.35 g Ba(NO2)2 • 4 mol O / 1 mol Ba(NO2)2 • 16.0 g O / 1 mol O = 12.8 g oxygen