Answer:
the answer is the option "a"
Explanation:
in petroleum polycyclic aromatic hydrocarbons are found. These organic compounds are composed of aromatic rings. PAH (Polycyclic Aromatic Hydrocarbons), are formed during the incomplete combustion of any type of organic matter. In general, exposure will be to a mixture of PAHs.
1a 1
b 4
c 5
2 (5.44x10^2)(2.5x10^-3)(7.9x10^-3) = 1.1x10^-6
3 750/1000 = 0.750
4 50/0.5 = 100 mL
5 He came up with the modern ideals for chemsitty
Answer:18.02 grams
The average mass of one mole of H2O is 18.02 grams.
Explanation: we need to find the moles of water in 1 L of water or 1000mL of water. Taking the density of water to be 1g/mL, 1000mL of water= 1000g water.
Therefore, number of moles= given mass of water(1000)/molecular mass of water(18)
Moles =1000/18= 55.55
So total molecules in 55.55 moles= 55.55* 6.022*10^23 = 334.52*10^23 molecules
=3.34*10^25 molecules of water.
:)
When copper(II) nitrate Cu(NO3)2 decomposition, the final products will determine by temperature. But the ratio of Cu(NO3)2 and NO2 is constant: 1:2. So mole number of 75 g is 0.4 mol. So NO2 is 0.8 mol and is 36.8 g.
Answer:
0.0375 moles HBr
Explanation:
we are given;
- Molarity of HBr solution as 0.15 M
- Volume of the solution as 250 mL
We are required to determine the number of moles;
We need to know that;
Molarity = Moles ÷ Volume
Therefore;
Moles of HBr = Molarity of HBr solution × Volume of solution
Thus;
Moles of HBr = 0.15 M × 0.25 L
= 0.0375 Moles
Thus, the number of moles of HBr solute is 0.0375 moles
