What causes the seasons?
The seasons are caused by the tilt of the Earth's rotational axis away or toward the sun as it travels through its year-long path around the sun.
The combustion reaction is as expressed,
CxHy + O2 --> CO2 + H2O
The mass fraction of carbon in CO2 is 3/11. Hence,
mass of C in CO2 = (3.14 g)(3/11) = 0.86 g C.
Given that we have 1 g of the hydrocarbon, the mass of H is equal to 0.14 g.
moles of C = 0.86 g C / 12 g = 0.0713
moles of H = 0.14 g H / 1 g = 0.14
The empirical formula for the hydrocarbon is therefore, CH₂.
I think it's Letter c.13 if I'm not mistaken
Answer:
Option B
Explanation:
As Brønsted-Lowry theory states, acids are the ones that can donate protons.
When a proton is donated, it is released to become medium more acidic.
HCl is a strong acid.
HCl (l) + H₂O (l) → H₃O⁺ (aq) + Cl⁻(aq)
These always reffers to strong acid where the dissociation is 100% completed.
In a weak acid, dissociation is not 100% complete, that's why we have an equilibrium.
HA (l) + H₂O (l) ⇄ H₃O⁺ (aq) + A⁻(aq) Ka
%yield = 88.5%
<h3>Further explanation</h3>
Given
Reaction
Cu(s) + 2 AgNO₃(aq) → Cu(NO₃)₂(aq) + 2Ag(s)
Required
The percent yield
Solution
mol AgNO₃(MW=169,87 g/mol) :
= mass : MW
= 127 : 169.87
= 0.748
mol Ag from equation :
= 2/2 x mol AgNO₃
= 2/2 x 0.748
= 0.748
Mass Ag (theoretical) :
= mol x Ar Ag
= 0.748 x 108
= 80.784
% yield = (actual/theoretical) x 100%
%yield = 71.5/80.784 x 100%
<em>%yield = 88.5%</em>
