1st one I think.........................
Answer:
Reflection: you look in the mirror. Refraction: You put a straw in a glass of water, and it looks like it broke. Absorption: If you have a black sweater and you wear it out in the cold, the black sweater is going to hold in heat better than a lighter sweater because the black sweater absorbs light .
Answer:
<h2>3.156 × 10²² atoms</h2>
Explanation:
To find the number of moles in a substance given it's number of entities we use the formula

where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have

We have the final answer as
<h3>3.156 × 10²² atoms</h3>
Hope this helps you
Answer:
The initial temperature was 58.4°C
Explanation:
Given the following data:
initial volume = V₁ = 380 mL = 0.38 L
final volume = V₂ = 250 mL = 0.25 L
final temperature = T₂ = -55°C = 218 K
According to Charles's law, the volume of a gas is <em>directly proportional to the temperature</em> (in Kelvin). The mathematical expression is:
V₁/T₁= V₂/T₂
So, we calculate the initial temperature (V₁) as follows:
T₁ = T₂/V₂ x V₁ = 218 K/(0.25 L) x 0.38 L = 331.36 K ≅ 331.4 K
Finally, we convert the initial temperature from K to °C:
T₁= 331.4 K - 273 = 58.4°C

1 mole of nitric acid produce 1 mole of ammonium nitrate.
moles in 5000 kg of ammonium nitrate :
( molecular mass of ammonium nitrate is 80 gm/mol )
So, number of moles of nitric acid required are also 62500 moles.
Mass of 62500 moles of nitric acid :

Hence, this is the required solution.