Answer:
145 grams of a 0.480 % KCN solution contains 697 mg of KCN.
Explanation:
w/w % : The percentage mass or fraction is mass of the of solute present in 100 grams of the solution.
given = w/w% = 0.480 %
Mass of solute that KCN = 697 mg = 0.697 g
(1 mg = 0.001 g)
Mass of the solution = ? = x
x = 145.21 g ≈ 145 g
145 grams of a 0.480 % KCN solution contains 697 mg of KCN.
4 NH₃ + 3O₂ --> 2N₂ + 6H₂O
First, make sure that this is a balanced equation.
There are 4 moles of nitrogen on the left side, and 4 moles of nitrogen on the right side.
There are 12 moles of hydrogen on the left side, and 12 moles of hydrogen on the right side.
There are 6 moles of oxygen on the left side, and 6 moles of oxygen on the right side.
The equation is therefore balanced, and we may proceed.
a) the mole ratio for NH₃ to N₂ is 4 to 2, which can be simplified to 2:1 or 2/1.
b) the mole ratio for H₂O to O₂ is 6 to 3, which can be simplified to 2:1 or 2/1.
False
explanation
All of the elements with atomic numbers 1 to 92 can be found in nature, have stable or very long half-life isotopes, and are created as common products of the decay of uranium and thorium.
Answer:
B
Explanation:
if it releases energy it becomes a solid(Solid)
if it absorbs energy it becomes a gas(Water Vapor)
Answer:
(a) 
(b)
(c) 
Explanation:
Hello,
(a) In this case, with the given formula we easily compute the mass of gold contained in the sovereign as shown below:
(b) Now, by knowing the density of gold and copper, 19.32 and 8.94 g/cm³ respectively, we compute each volume, by also knowing that the rest of the coin contains copper:
(c) Finally, the volume is computed by dividing the total mass over the total volume containing both gold and copper:
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