Answer:
The oxygen produced is collected in the gas jar by downward displacement of water. When we insert the glowing matchstick in the jar containing the oxygen gas ,it burns with a bright light which proves that gas is oxygen because oxygen is supporter of combustion.
Answer:
39.7 %
Explanation:
magnesium + oxygen ⟶ magnesium oxide
10.57 g 6.96 g 17.53 g
According to the <em>Law of Conservation of Mass</em>, the mass of the product must equal the total mass of the reactants.
Mass of MgO = 10.57 + 6.96
Mass of MgO = 17.53 g
The formula for mass percent is
% by mass = Mass of component/Total mass × 100 %
In this case,
% O = mass of O/mass of MgO × 100 %
Mass of O = 6.96 g
Mass of MgO = 17.53 g
% O = 6.96/17.53 × 100
% O = 0.3970 × 100
% O = 39.7 %
Answer:
K = 361.369
Explanation:
C2H4(g) + H2O(g) → CH3CH2OH(g)
∴ ΔG°f(298.15K) CH3CH2OH(g) = - 174.8 KJ/mol
∴ ΔG°f(298.15) C2H4(g) = 68.4 KJ/mol
∴ ΔG°f(298.15) H2O(g) = - 228.6 KJ/mol
⇒ ΔG°f(298.15) = - 174.8 - ( - 228.6 + 68.4 ) = - 14.6 KJ/mol
∴ R = 8.314 E-3 KJ/mol.K
∴ T = 298.15 K
⇒ K = e∧(-(-14.6)/((8.314 E-3)(298.15)))
⇒ K = e∧(5.889)
⇒ K = 361.369
Answer:
Okay, Left top= waning gibbous
left second= new moon
left third= third quarter
left fourth= waxing crescent
right top= Waning crescent
right second= first quarter
right third= full moon
right fourth= Waxing gibbous
hope you do good :)
Answer:
The darkness of the green color produced in the beakers is different because the concentration of magnesium hydroxide is different in both beakers.
Explanation:
The reason why the flasks have different color intensity is related to the concentration of magnesium hydroxide.
An indicator usually changes color because its conformation changes according to the pH. The higher the base level, the pH is higher. Then the color shift will be more intense.
Beaker A has 20 ml of magnesium hydroxide and 100 ml of water and beaker B has 50ml of magnesium hydroxide and 100ml of water.
Beaker A is more diluted than beaker B.
Therefore, beaker B is greener than beaker A.