Thank you for posting your question here at brainly. Below is the solution:
<span>moles HClO4 = 0.100 L x 0.18 M = 0.018
moles LiOH = 0.030 L x 0.27 = 0.0081
moles H+ in excess = 0.018 - 0.0081 = 0.0099
total volume = 0.130 L
[H+] = 0.0099/ 0.130= 0.0762 M
pH = 1.12</span>
In order to calculate the number of atoms, we must first know the number of moles present. And
moles = (mass present) / (molecular mass)
Therefore, the moles of Mg present are
170 / 24 = 7.08
The number of atoms in a mole of substance is given by Avagadro's Number which is 6.02 x 10^23
Since there are 7.08 moles, there are:
7.08 * 6.02*10^23
= 4.26 * 10^24 atoms
2.77mg caffeine / 1oz12oz / 1canLethal dose: 10.0g caffeine = 10,000mg caffeine First, find how much caffeine is in one can of soda, then divide that amount by the lethal dose to find the number of cans. (2.77mg caffeine / 1oz) * (12oz / 1can) = 33.24mg caffeine / 1can. (10,000mg caffeine) * (1can / 33.24mg caffeine) = 300.84 cans. Since we can't buy parts of a can of soda, then we have to round up to 301 cans. Notice how all the values were set up as ratios and how the units cancelled.
Answer:
Thus,there are 0.2 mole in 8 g of calcium.