Answer:
Answer: a) 20g of H2O (18.02 g/mol) molecules=6.68x10^23
Explanation:
In order to find the amount of molecules of each of the options, we need to follow the following equation.
![molecules=\frac{mass(g)x6.022x10^{23}(molecules/mol) }{atomic weight(g/mol)}](https://tex.z-dn.net/?f=molecules%3D%5Cfrac%7Bmass%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7Batomic%20weight%28g%2Fmol%29%7D)
So, let´s get the number of molecules for each of the options.
![a) molecules=\frac{20(g)x6.022x10^{23}(molecules/mol) }{18.02(g/mol)}=6.68x10^{23}molecules](https://tex.z-dn.net/?f=a%29%20molecules%3D%5Cfrac%7B20%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7B18.02%28g%2Fmol%29%7D%3D6.68x10%5E%7B23%7Dmolecules)
![b) molecules=\frac{77(g)x6.022x10^{23}(molecules/mol) }{16.06(g/mol)}=2.89x10^{24}molecules](https://tex.z-dn.net/?f=b%29%20molecules%3D%5Cfrac%7B77%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7B16.06%28g%2Fmol%29%7D%3D2.89x10%5E%7B24%7Dmolecules)
![c) molecules=\frac{68(g)x6.022x10^{23}(molecules/mol) }{42.09(g/mol)}=9.73x10^{23}molecules](https://tex.z-dn.net/?f=c%29%20molecules%3D%5Cfrac%7B68%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7B42.09%28g%2Fmol%29%7D%3D9.73x10%5E%7B23%7Dmolecules)
![d) molecules=\frac{100(g)x6.022x10^{23}(molecules/mol) }{44.02(g/mol)}=1.37x10^{24}molecules](https://tex.z-dn.net/?f=d%29%20molecules%3D%5Cfrac%7B100%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7B44.02%28g%2Fmol%29%7D%3D1.37x10%5E%7B24%7Dmolecules)
![d) molecules=\frac{84(g)x6.022x10^{23}(molecules/mol) }{20.01(g/mol)}=2.53x10^{24}molecules](https://tex.z-dn.net/?f=d%29%20molecules%3D%5Cfrac%7B84%28g%29x6.022x10%5E%7B23%7D%28molecules%2Fmol%29%20%7D%7B20.01%28g%2Fmol%29%7D%3D2.53x10%5E%7B24%7Dmolecules)
the smalest number is in option a)
Best of luck.
Step 1 : write a valanced equation..
NaOH + HCl 》NaCl + H2O
Step 2 : find the number of mole of HCl..
1000 ml ..contains 4.3 mole
15ml... (4.3÷1000)×15 =...
Stem 3 : use mole ratio....
HCl : NaOH
1 : 1
So mole is same as calculated above...
Step 4 :
3.5 mole of NaOH is in 1000ml
(4.3÷1000)×15 mole is in ....
Do the calculation
1.8 L
<h3>
Explanation</h3>
The volume of a gas, V, is inversely proportional to the pressure on it, P. That is:
V₁ · T₁ = V₂ · T₂.
Rearranging gives:
V₂ = V₁ · T₁ / T₂ = 4.2 × (101 / 235) = 1.8 L
I think it’s the third option but I’m not entirely sure