Answer:
b. 50ppm of Pb
c. 2x10⁻⁴M
j. no
Explanation:
The diluted sample has a concentration of 0.5 ppm of Pb. The sample was diluted from 1mL to 100mL. That means the dilution factor is:
100mL / 1mL = 100
That means, the sample was diluted 100 times from its original concentration.
As diluted sample has a concentration of 0.5ppm, the undiluted sample has a concentration of
0.5ppm×100 = <em>50ppm of Pb</em>
1 ppm means 1x10⁻⁴ % by mass, 50 ppm are 50x10⁻⁴ % by mass
As molar mass of Pb is 207g/mol, molarity of 0.050g / L a(50 ppm) are:
0.050gₓ (1mol / 207g) / 1L = <em>2x10⁻⁴M</em>
<em></em>
Based on EPA regulation, the maximum concentration of Lead in drinking water must be 0.015ppm. That means this water <em>is not safe to drink</em>
Answer: A sulfur ion has more electron shells than a chlorine ion.
Answer:
pH= 8.45
Explanation:
when working with strong accids pH = -log(Concentration)
so -log(3.58e-9) = 8.446
Answer:
10 moles
Explanation:
of moles = given mass /atomic mass = 280 g /28 g = 10 moles of Si atoms in 280g sample.
Two [hydrogen] atoms and one [oxygen] atom
