Answer:
the heat given off is 75 J.
Explanation:
Given;
latent heat of fusion of lead, L= 25 J/g
mass of liquid lead, m = 3.0g
The heat given off is calculated as;
H = Lm
Where;
H is the quantity of heat given off
H = 25 x 3
H = 75 J.
Therefore, the heat given off is 75 J.
Answer:
Sodium and chlorine combine to make salt
Explanation:
Answer:
<h2>0.5 moles</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>0.5 moles</h3>
Hope this helps you
Filtration<span>, Reabsorption, Secretion: The Three </span>Steps<span> of Urine Formation. The kidneys </span>filter<span> unwanted substances from the blood and produce urine to excrete them. There are three main </span>steps<span> of urine formation: glomerular </span>filtration<span>, reabsorption, and secretion.</span>
On temperature 25°C (298,15K) and pressure of 1 atm each gas has same amount of substance:
n(gas) = p·V ÷ R·T = 1 atm · 20L ÷ <span>0,082 L</span>·<span>atm/K</span>·<span>mol </span>· 298,15 K
n(gas) = 0,82 mol.
1) m(He) = 0,82 mol · 4 g/mol = 3,28 g.
d(He) = 10 g + 3,28 g ÷ 20 L = 0,664 g/L.
2) m(Ne) = 0,82 mol · 20,17 g/mol = 16,53 g.
d(Ne) = 26,53 g ÷ 20 L = 1,27 g/L.
3) m(CO) = 0,82 mol ·28 g/mol = 22,96 g.
d(CO) = 32,96 g ÷ 20L = 1,648 g/L.
4) m(NO) = 0,82 mol ·30 g/mol = 24,6 g.
d(NO) = 34,6 g ÷ 20 L = 1,73 g/L.