Question

3.65 gram of hcl is dissolved in 180 gram of water. Find the total number of molecules of hydrogen​

Answer 1

`Molec_{\ H_(tot)}=1.206x10^(25)molec`

Step-by-step explanation:

Hello.

In this case, taking into account that HCl has one molecule of hydrogen per mole of compound which weights 36.45 g/mol, we compute the number of molecules of hydrogen in hydrochloric acid by considering the given mass and the Avogadro's number:

`molec_(\ H)=3.65gHCl*(1molHCl)/(36.45gHCl) *(1molH)/(1molHCl)*(6.022x10^(23)molec_\ H)/(1molH) =6.03x10^(22)molec`

Now, from the 180 g of water, we see two hydrogen molecules per molecule of water, thus, by also using the Avogadro's number we compute the molecules of hydrogen in water:

`molec_(\ H)=180gH_2O*(1molH_2O)/(18gH_2O) *(2molH)/(1molH_2O)*(6.022x10^(23)molec_\ H)/(1molH) =1.20x10^(25)molec`

Thus, the total number of molecules turns out:

`Molec_{\ H_(tot)}=6.03x10^(22)+1.20x10^(25)\\\\Molec_{\ H_(tot)}=1.206x10^(25)molec`

Regards.