Answer:
151.4863 years
Explanation:
Half life, t1/2 = 100 years
Initial concentration,[A]o = 100%
Final concentration, [A] = 35% (after 65% have been decayed)
Time = ?
Half life for a first Order reaction is given as;
t1/2 = ln (2) / k
k = ln(2) / 100
k = 0.00693y-1
The integral rate law for first order reactions is given as;
ln[A] = ln[A]o − kt
kt = ln[A]o - ln[A]
t = ( ln[A]o - ln[A]) / k
t = [ln(100) - ln(35)] /0.00693
t = 1.0498 / 0.00693
t = 151.4863 years
Explanation:
The smaller numbers in the image below represents the <u>subscripts</u>.
Answer: Oil: covalent
Cornstarch: Covalent
Sodium chloride: Ionic
Sodium bicarbonate: Ionic
Explanation: Covalent compounds are formed by sharing of electrons between non metals whereas ionic compounds are formed by transfer of electrons from metals to non metals.
1. Oil, which is built from the nonmetals hydrogen, carbon, and oxygen: forms a covalent compound by sharing of electrons between non metals hydrogen, carbon, and oxygen. Covalent compounds are insoluble in water.
2. Cornstarch, a carbohydrate consisting of hydrogen, carbon, and oxygen: forms a covalent compound by sharing of electrons between non metals hydrogen, carbon, and oxygen. Covalent compounds are insoluble in water.
3. Sodium chloride (table salt), whose formula is NaCl is formed by transfer of electrons from sodium to chlorine.Ionic compounds are soluble in water.
4. Sodium bicarbonate, whose formula is
is formed by transfer of electrons from sodium to
.Ionic compounds are soluble in water.
Answer:
a. -29.8 kJ/mol-rxn
Explanation:
For a chemical reaction system the forward and reverse rate are equal. The standard molar enthalpy formation of NH3 is -45.9 kJ/mol. For the enthalpy of NH3 (8) the molar enthalpy is -29.8kJ/mol. The molar mass of N2 = 28.02g/mol. Molar enthalpy of formation is standard amount of substance produced in the formation of a reaction. The molar enthalpy is the change in enthalpy due to reaction per mole.
Answer:
354.67K
Explanation:
Applying
P₁V₁/T₁ = P₂V₂/T₂................. Equation 1
Where Where P₁ = initial pressure, T₁ = Initial temperature, V₁ = Initial Volume, P₂ = Final pressure, V₂ = Final Volume, T₂ = Final Temperature.
From the question, we are ask to look for the final temperature,
Therefore we make T₂ the subject of the equation
T₂ = P₂V₂T₁/P₁V₁............. Equation 2
Given: P₁ = 600 kPa, V₁ = 500 mL, T₁ = 77 °C = (273+77) = 350 K, P₂ = 760 kPa, V₂ = 400.0 mL
Substitute these values into equation 2
T₂ = (760×400×350)/(600×500)
T₂ = 354.67 K