Answer:
what is this I am not getting which type of this question you have taken from where
It is so because warm air is lighter than cold air. Cold air means the molecules are not moving as much, so they will feel like sticking together and will not jump around as molecules in warm air will(higher temp. means higher KE). Think of a solid, colder solids are much heavier than warmer ones(think of ice-starts melting).
Mass of SiC = 2 g
<h3>Further explanation</h3>
Given
Reaction
SiO₂(s) + 3C(s) → SiC(s) + 2CO(g)
3.00 g of SiO₂
4.50 g of C
Required
mass of SiC
Solution
mol SiO₂ (MW=60,08 g/mol) :
= 3 g : 60.08 g/mol
= 0.0499
mol C(Ar = 12 g/mol) :
= 4.5 g : 12 g/mol
= 0.375
mol : coefficient of reactants =
SiO₂ : 0.0499/1 = 0.0499
C : 0.375/3 = 0.125
SiO₂ as a limiting reactant(smaller ratio)
Mol SiC based on mol SiO₂ = 0.0499
Mass SiC :
= mol x MW
= 0.0499 x 40,11 g/mol
= 2 g
Answer: -2m/s2
Explanation:
Using the following equation ; acceleration = Change in velocity / time
i.e a = v - u / t
where 'a' = acceleration
v = final velocity
u = initial velocity
t = time
Therefore; from the graph we have acceleration to be, 0 - 6m/s / 3s = -2m/s2