Answer:
B
Explanation:
"I think my bike is making a scraping noise because the bearings are not lubricated."
Answer:
= 97.44 Liters at S.T.P
Explanation:
The reaction between Iron (iii) oxide and Carbon monoxide is given by the equation;
Fe2O3(s)+ 3CO(g) → 3CO2(g) + 2Fe(s)
From the reaction when the reactants react, 2 moles of Fe and 3 moles of CO2 are produced.
Therefore; Mole ratio of Iron : Carbon dioxide is 2:3
Thus; Moles of Carbon dioxide = (2.9/2)×3
= 4.35 moles
But; 1 mole of CO2 at s.t.p occupies 22.4 liters
Therefore;
Mass of CO2 = 22.4 × 4.35 Moles
= 97.44 L
Answer:
d. white blood cells
Explanation:
It is the white blood cells that have the least tendency to cross the blood- brain barrier.
Blood- brain barrier is psychological barrier and restricts substances that circulate into the blood from crossing over the central nervous system.
Water, glucose as well as sodium ions can easily cross the barrier. As these are good for body supply energy to the brain.
Answer:
15.2 g H2
Explanation:
2H2O -> 2H2 + O2
9.06 x 10^24 molecules x (1 mol/6.022 x 10^23 molecules) x (2 mol H2/2 mol H2O) x (1.008 g/1 mol) = 15.2 g H2
