Answer:
9 days, or 3 half-lives
Explanation:
5.2x10^5=520000
6.5x10^4=65000
65000/520000=1/8, or 3 half-lives
3x3=9 days
I'm not the greatest at Chem but this seems more like math than Chem :)
Answer:
818.2 g.
Explanation:
- Molarity is the no. of moles of solute per 1.0 L of the solution.
<em>M = (no. of moles of NaCl)/(Volume of the solution (L))</em>
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M = 2.0 M.
no. of moles of NaCl = ??? mol,
Volume of the solution = 7.0 L.
∴ (2.0 M) = (no. of moles of NaCl)/(7.0 L)
∴ (no. of moles of NaCl) = (2.0 M)*(7.0 L) = 14.0 mol.
- To find the mass of NaCl, we can use the relation:
<em>no. of moles of NaCl = mass/molar mass</em>
<em></em>
<em>∴ mass of NaCl = (no. of moles of NaCl)*(molar mass) =</em> (14.0 mol)*(58.44 g/mol) = <em>818.2 g.</em>
The choices are true about the characteristic of a strong base, except for it having a concentration of above 1.0 M. Therefore, the answer is letter A. The concentration of the base is not a very important as to how strong really the base is.
Answer:
5.56 moles H₂O
Explanation:
moles = mass of substance / formula weight of substance
∴moles H₂O = 100 grams / 18 grams/mole = 5.56 moles H₂O
Answer:
the answer is d. 1/5 because if you times the bottom number by 20 you will get 100 and the top number wil be a 20 which is 20%