First of all, as you seen the gases are noble which means that will not react with each other and in this case each gas create individual pressure.
P
= total pressure
P
= pressure of neon
P
= pressure of argon
P
= pressure of helium {which is required}
P
= P
+ P
+ P
1.25 = 0.68 + 0.35 + P
P
= 1.25 - [0.68 + 0.35] = 0.22 atm
The answer is 42 grams of NaF are there in 1 mole.
<h3>
What is a mole ?</h3>
A mole is defined as 6.022 × 10²³ atoms, molecules, ions, or other chemical units.
and the molar mass of a substance is defined as the mass of 1 mole of that substance, expressed in grams per mole.
It is equal to the mass of 6.022 × 10²³ atoms, molecules, or formula units of that substance.
Molar Mass , i.e. mass of 1 mole of NaF is sum of molar mass of Na and F
23 + 19
42 grams
Therefore 42 grams of NaF Sodium-fluoride are there in 1 mole.
To know more about mole
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<span> the atmosphere holds about 21 per cent oxygen. Over the Earth’s 4.6 billion year history, oxygen did not appear in the atmosphere until perhaps about 2.5 billion years ago. Since then, oxygen levels have fluctuated in tandem with global geological and biological events, such as mass extinctions.</span>
Answer:
a) 0.210 j
/k
b) 0.032 j/k
Explanation:
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