Volume of each solution : 60 ml 20% and 40 ml 45%
<h3>Further explanation</h3>
Given
20% and 45% acid
100 ml of 30% acid
Required
Volume of each solution
Solution
Molarity from 2 solutions :
Vm Mm = V₁. M₁ + V₂. M₂
m = mixed solution
V = volume
M = molarity
V₁ = x ml
V₂ = (100 - x) ml
Input the value :
100 . 0.3 = x . 0.2 + (100-x) . 0.45
30 = 0.2x+45-0.45x
0.25x=15
x= 60 ml
V₁ = 60 ml
V₂ = 100 - 60 = 40 ml
Na₂S(aq) + Cd(NO₃)₂(aq) = CdS(s) + 2NaNO₃(aq)
v=25.00 mL
c=0.0100 mmol/mL
M(Na₂S)=78.046 mg/mmol
n(Na₂S)=n{Cd(NO₃)₂}=cv
m(Na₂S)=M(Na₂S)n(Na₂S)=M(Na₂S)cv
m(Na₂S)=78.046*0.0100*25.00≈19.5 mg
Answer: (3) 15
Explanation: We criss-cross down the oxidation numbers to get the subscripts for the correct formulas. That means the X has an oxidation number of 5. The element with the + oxidation number is always written first so it is +5. Of the groups names, only group 15 has +5 as an oxidation number.
Answer:

Explanation:
Hello,
In this case, we can compute the change in the solution enthalpy by using the following formula:

Whereas the mass of the solution is 350 g, the specific heat capacity is 4.184 J/g °C and the change in the temperature is 1.34 °C, therefore, we obtain:

It is important to notice that the mass is just 350 g that is the reacting amount and by means of the law of the conservation of mass, the total mass will remain constant, for that reason we compute the change in the enthalpy as shown above, which is positive due to the temperature raise.
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