A large volume of material will have a small amount of mass when the
material in question is gaseous or porous, and therefore has a lot of
space within it despite taking up a large amount of space overall.
Answer:
12 grams of hydrogen gas
and 56 grams of nitrogen gas
The molar mass of ammonia is 17 g/mol.
68 grams of ammonia corresponds to
17g/mol
68g
=4moles
4 moles of ammonia will be obtained from
2
4×1
=2 moles of nitrogen and
2
4×3
=6 moles of hydrogen.
The molar masses of nitrogen and hydrogen are 28 g/mol and 2 g/mol respectively.
2 moles of nitrogen corresponds to 2×28=56 grams.
6 moles of hydrogen corresponds to 6×2=12 grams.
The answer is A. Na
because it's<span /> 5,1391
Explanation:
2-metylbutene should be the profuct
Answer:
D. -120.9 kJ
Explanation:
According to Hess's law ,the total enthalpy change for a reaction is the sum of all changes regardless of the stages or the steps of the reaction.
....(1)
(this reaction should be reversed in order to reach the required reaction )
On reversing the reaction the sign of 
get reversed.
(In this case change sign from '-' to'+'. Hence = + 65 kJ)
....(1)
......(2)
Adding equation (1) and (2)
![Ca(OH)_{2} + 2HCl \rightarrow CaCl_{2} + 2H_{2}O[tex][tex]Delta H = - 186 + 65 = - 121\kJ](https://tex.z-dn.net/?f=%3Cstrong%3ECa%28OH%29_%7B2%7D%20%2B%202HCl%20%5Crightarrow%20CaCl_%7B2%7D%20%2B%202H_%7B2%7DO%3C%2Fstrong%3E%5Btex%5D%3C%2Fp%3E%3Cp%3E%5Btex%5D%3Cstrong%3EDelta%20H%20%3D%20-%20186%20%2B%2065%20%3D%20-%20121%5CkJ%3C%2Fstrong%3E)
(It is nearly equal to -120.9 kJ)
