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Answer:</h2>
<h3>From the equation it is evident that 2 moles of Sodium metal produces 1 mole of hydrogen gas.</h3><h3>At STP 1mole of any gas occupies a volume of 22.4 litres.</h3><h3>Therefore, 7.80 gives---(7.80x1)/22.4 moles = 0.3482 moles</h3><h3>Since the mole ratio of Sodium to hydrogen is 2:1, then the number of moles of sodium that reacted is given by the following expression.</h3><h3>(0.3482 * 2) / 1 moles which gives 0.6964 moles.</h3><h3>The atomic mass of sodium is 23 thus the mass of sodium that reacted is given by:</h3><h3>mass=no. of Monogram</h3><h3>0.6964 * 23 = 16.02 grams.</h3><h2>
Explanation:</h2><h3>please mark me brainlist</h3>
Atomic mass <span>of zinc ( zn ) is 65 u
Answer B</span>
I’m pretty sure it’s 150 joules
Given :
Number of molecules of hydrogen peroxide, N = 4.5 × 10²².
To Find :
The mass of given molecules of hydrogen peroxide.
Solution :
We know, 1 mole of every compound contains Nₐ = 6.022 × 10²³ molecules.
So, number of moles of hydrogen peroxide is :

Now, mass of hydrogen peroxide is given as :
m = n × M.M
m = 0.0747 × 34 grams
m = 2.54 grams
Hence, this is the required solution.