Answer:
My conclusion about the picture above. Is cleaning or arrange all things in the kitchen is one of the reason to avoid us in danger.The things that we can prevent danger in the kitchen always clean the kitchen room,things especially to a hazard things.
burning is one of danger things that happrn in the kitchen.
Answer:
See the answers below
Explanation:
1) 100. mL of solution containing 19.5 g of NaCl (3.3M)
2) 100. mL of 3.00 M NaCl solution (3 M)
3) 150. mL of solution containing 19.5 g of NaCl (2.2 M)
4) Number 1 and 5 have the same concentration (1.5M)
MW of NaCl = 23 + 36 = 59 g
For number 3
59 g ------------------- 1 mol
19,5 g ----------------- x
x = 19.5 x 1/59 = 0.33 mol
Molarity (M) = 0.33 mol/0.150 l = 2.2 M
For number 4,
Molarity (M) = 0.33mol/0.10 l = 3.3 M
For number 5
Molarity (M) = 0.450/0.3 = 1.5 M
Answer:
You can change an object's state of matter by adding or removing thermal energy. When you add thermal energy to an object, these things can happen: Particles move faster
Explanation:
Finding percent composition is fairly easy. You only need to divide the mass of an element by the total mass of the compound. We can do this one element at a time.
First, let's find the total mass by using the masses of the elements given on the periodic table.
7 x 12.011 (mass of Carbon) = 84.077
5 x 1.008 (mass of Hydrogen) = 5.04
3 x 14.007 (mass of Nitrogen) = 42.021
6 x 15.999 (mass of Oxygen) = 95.994
Add all of those pieces together.
84.077 + 5.04 + 42.021 + 95.994 = 227.132 g/mol is your total. Since we also just found the mass of each individual element, the next step will be very easy.
Carbon: 84.077 / 227.132 = 0.37016 ≈ 37.01 %
Hydrogen: 5.04 / 227.132 = 0.022189 ≈ 2.22 %
Nitrogen: 42.021 / 227.132 = 0.185 ≈ 18.5 %
Oxygen: 95.994 / 227.132 = 0.42263 ≈ 42.26 %
You can check your work by making sure they add up to 100%. The ones I just found add up to 99.99, which is close enough. A small difference (no more than 0.03 in my experience) is just a matter of where you rounded your numbers.
