## Calculation problem

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ned_yas
Newbie
Posts: 3
Joined: Mon Nov 01, 2021 3:45 am

### Calculation problem

Hi people,

I'm trying to solve the following problems:

Problem 1:
1) How many grams HCl with mass fraction ω=36,5 % will fully dissolve 6 g Mg?
2) What's the mass fraction ω of MgCl2 in the formed solution?

For 1) I've calculated that 18,25 g HCl will fully react 6 g Mg - is this correct?
For 2) will the MgCl2 solution have ω=36,5 %? - is this correct?

Problem 2:
How many grams HCl with ω=30 % are needed to neutralise 500 ml NaOH solution with density ρ=1,2 g/ml and ω(NaOH)=10 %?
My calculations give 182,5 g HCl needed to neutralise the given amount of NaOH - is this correct?

Thanks for verifying and helping in advance.

Greetings,
Ned
ChenBeier
Distinguished Member
Posts: 974
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Calculation problem

1) you calculated the 100% of HCl, not 36,5%
Second one is also wrong
2) is correct
ned_yas
Newbie
Posts: 3
Joined: Mon Nov 01, 2021 3:45 am

### Re: Calculation problem

Yes, many thanks @ChenBeier - meantime I realised my mistake and corrected - it should be for 1) 50 g solution of HCl, and for 2) 42,8 % MgCl2

Greetings,
Ned
ChenBeier
Distinguished Member
Posts: 974
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Calculation problem

Now it is correct.
ned_yas
Newbie
Posts: 3
Joined: Mon Nov 01, 2021 3:45 am

### Re: Calculation problem

ChenBeier wrote: Mon Nov 01, 2021 10:57 am Now it is correct.
Many thanks for confirming!