Answer:
4.65 g x 1 mol/4.0026 g/mol = 1.162 mol helium
Explanation:
Answer:
CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺
Explanation:
A buffer is defined as the mixture of a weak acid and its conjugate base or vice versa.
For the acetic acid buffer, CH₃CO₂H is the weak acid and its conjugate base is the ion without H⁺, that is CH₃CO₂⁻. The equilibrium equation in water knowing this is:
<h3>CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺</h3>
<em>In the equilibrium, the acid is dissociated in the conjugate base and the hydronium ion.</em>
Answer:
B. 0.2.
Explanation:
<em>n = mass/molar mass</em>
mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.
<em>∴ n = mass/molar mass = </em>(20 g)/(100.0869 g/mol) <em>= 0.1998 ≅ 0.2 mol.</em>
<em></em>
<em>So, the right choice is: B. 0.2.</em>
Answer:
g/cm³ for solids,
g/ml for liquids
g/L for gases.
Explanation:
Though SI unit of density is kg/m³, for convenience we use g/cm³ for solids, g/ml for liquids and g/L for gases. Mathematically, density is defined as mass divided by volume:
ρ=m/V
Answer:
C.Melt both cubes and look for a broader range of melting temperatures. The one that melts over a broader range of temperatures is the amorphous solid.
Explanation:
Amorphous solids is one that do not have a fixed melting points but melt over a wide range of temperature due to the irregular shape hence its name. Contrariwise crystalline solids, have a fixed and sharp melting point.
This comes in handy to solve the riddle. We can characterise the pair with the melting point property.
