Answer:
I believe it is A
Explanation:
pH = -log[H+] and pOH = -log[OH−].
Given :
A 250 ml beaker weighs 13.473 g .
The same beaker plus 2.2 ml of water weighs 15.346 g.
To Find :
How much does the 2.2 ml of water, alone, weigh .
Solution :
Now, mass of water is given by :

Therefore , mass of 2.2 ml of water alone is 1.873 g .
Hence , this is the required solution .
Hey there!
To calculate the percent by mass of the Ca(NO₃)₂ we need to find the total mass first by adding.
896.92 + 22.63 = 919.55
In total, the solution is 919.55 grams.
To find the percent of Ca(NO₃)₂ in the solution, divide the mass of Ca(NO₃)₂ by the total mass and multiply by 100.
22.63 ÷ 919.55 = 0.0246
0.0246 x 100 = 2.46
Ca(NO₃)₂ makes up 2.46% of the solution.
Hope this helps!