The mass of iron block is 500 g. The amount of energy required to melt the iron block needs to be calculated. Melting means conversion of solid to liquid thus, heat of fusion is used which is 247 J/g.
From heat of fusion, 247 J of energy is released by melting 1 g of iron block. Thus, the amount of heat released by melting 500 g of iron rod will be:
H= 247 J/g× 500 g=1.23×10^{5}
Hence, option B is correct.
Convert moles to mass.
mass C = 0.2 mol * 12 g / mol = 2.4 g
mass H = 0.4 mol * 1 g / mol = 0.4 g
So mass left for O = 6 g – (2.4 g + 0.4 g) = 3.2 g
Calculating for moles O given mass:
moles O = 3.2 g / (16 g / mol) = 0.2 moles
Answer:
<span>0.2 moles O</span>
Answer:
The value of the silver in the coin is 35.3 $
Explanation:
First of all, let's calculate the volume of the coin.
2π . r² . thickness = volume
r = diameter/2
r = 41 mm/2 = 20.5 mm
2 . π . (20.5 mm)² . 2.5 mm = 6601 mm³
Now, this is the volume of the coin, so we must find out how many grams are on it.
6601 mm³ / 1000 = 6.60 cm³
Let's apply density.
D = Mass / volume
10.5 g/cm³ = mass /6.60 cm³
10.5 g/cm³ . 6.60 cm³ = mass
69.3 g = mass
Each gram has a cost of 0.51$
69.3 g . 0.51$ = 35.3 $
The whole Activity , poem and paragraph is missing in the question.
Answer:
(1) Liquid A
(2) Solid A
Explanation:
Using this part of the given poem
Substances and mixtures behave differently,
During boiling and melting most especially
Boiling point of substance is fixed while mixture is not
Substance melts completely but mixture does not
The boiling point of the Pure substance remain fixed after reaching its boiling point this is shown by Liquid A
Solid A is melting completely so Solid A is a pure substance.
