Answer:
14 ml of water
Explanation:
To find the volume you need to dilute the concentration of a solution, you should use the formula C1 x V1 = C2 x V2 in which:
C1 = initial concentration ( in this case 60 %)
V1 = initial volume ( in this case 70 ml)
C2 = Final concentration ( you want to dilute until 50 %)
V2 = final volume ( the variable you want to search)
So you need to:
1.- Isolate the variable you want to find: V2 = (C1 x V1) / C2
2.- Substitute data: V2 = (60% x 70 ml) /50 %
3.- You do the math, in this case is 84 ml.
4.- Remember that you have a initial volume of 70 ml, so the difference (84 ml - 70 ml = 14 ml) is the volume you need to add to dilute your solution.
Answer:
Acid.
Explanation:
I assume you mean 4.5?
pH below 7 is acidic
pH above 7 is alkaline
pH equal to 7 is neutral
4.5 lies below 7, so it is acidic
3.6*10^20 atoms* (1 mol/ (6.02*10^23 atoms))= 6.0*10^(-4) mol.
6.0*10^(-4) mol* (28.1 g/ 1 mol)= 1.7*10^(-2) g.
Note that the units cancel out so you get the answer.
The final answer is 1.7*10^(-2) g Si.
Answer:
Explanation:
Initial burette reading = 1.81 mL
final burette reading = 39.7 mL
volume of NaOH used = 39.7 - 1.81 = 37.89 mL .
37.89 mL of .1029 M NaOH is used to neutralise triprotic acid
No of moles contained by 37.89 mL of .1029 M NaOH
= .03789 x .1029 moles
= 3.89 x 10⁻³ moles
Since acid is triprotic , its equivalent weight = molecular weight / 3
No of moles of triprotic acid = 3.89 x 10⁻³ / 3
= 1.30 x 10⁻³ moles .
