Answer:
Explanation:
When water becomes a solid, it releases heat, warming up its surroundings. This makes freezing an exothermic reaction.
So the correct answer is True
Polyester and polyamide would be two synthetic polymers, created by condensation reaction.
Answer:A fossil is the remains or traces of a once-living plant or animal that was preserved in rock or other material before the beginning of recorded history. ... Fossils of single-celled organisms have been recovered from rocks as old as 3.5 billion years. Animal fossils first appear in rocks dating back about 1 billion years.
Explanation:
<h3>Answer:</h3>
Selenium has the greatest density at STP.
<h3>Explanation:</h3>
According to Ideal gas equation,
P V = n R T
where;
n = m/M
Therefore,
P V = m R T / M
Rearranging,
P M = (m/V) R T
Also,
m/V = density = d
So,
P M = d R T
Solving for density,
d = P M / R T
According to this equation density is directly proportional to Molar mass of a substance. Hence, the Atomic masses of given compounds are listed below,
Scandium = 44.96 g.mol⁻¹
Selenium = 78.97 g.mol⁻¹
Silicon = 28.09 g.mol⁻¹
Sodium = 22.99 g.mol⁻¹
Therefore, selenium having the greatest Atomic Mass will have the greatest density. The densities of given elements are as follow;
Scandium = 2.98 g.cm⁻³
Selenium = 4.81 g.cm⁻³
Silicon = 2.33 g.cm⁻³
Sodium = 0.96 g.cm⁻³
