Answer:
164 g
Explanation:
producers flowing from the bottom level to primary consumers. What
happens to the other 90% of the energy?
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The remaining 90% is transformed for life activities such as movement, growth, or
released as heat.
The remaining 90% evaporates into the atmosphere.
The remaining 90% transforms into Hydrogen and Oxygen.
The remaining 90% is recombined to maker larger molecules.
Answer: pH = 1.19
Explanation:
The formula for Ka is: Ka = [H+][A-]/[HA]
where: [H+] = concentration of H+ ions
[A-] = concentration of conjugate base ions
[HA] = concentration of undissociated acid molecules
Equation of reaction: Cl₂CHCOOH ---> H+ + Cl₂CHCOO-
From the equation above, dichloroacetic acid dissociates one H+ ion for every Cl₂CHCOO- ion,
so [H+] = [Cl₂CHCOO-].
Let x represent the concentration of H+ that dissociates from HA, then [HA] = C - x where C is the initial concentration.
Substituting these values into the Ka equation:
Ka = x · x / (C -x)
Ka = x²/(C - x)
(C - x)Ka = x²
x² = CKa - Kax
x² + Kax - CKa = 0
Solve for x using the quadratic formula:
x = [-b ± √(b² - 4ac)]/2a
Note: There are two solutions for x. However only the positive value of x is used since x represents a concentration of ions in solution, and so cannot be negative.
x = [-Ka + √(Ka² + 4CKa)]/2
Substitute the values for Ka and C in the equation above:
Ka = 5.0 x 10^-2
C = 0.15 M
x = {-5.0 x 10^-2 + √[(5.0. x 10^-2)² + 4(0.15)(5.0 x 10^-2)]}/2
x = (-5.0 x 10^-2 + 1.80 x 10^-1)/2
x = 0.13/2
x = 6.50 x 10^-2
To find pH, we use the formula;
pH = -log[H+]
pH = -log(x)
pH = -log(6.50 x 10^-2)
pH = -(-1.19)
pH = 1.19
Answer:
Average atomic mass = 19.9 amu
Explanation:
Isotopes can be defined as two or more forms of a chemical element that are made up of equal numbers of protons and electrons but different numbers of neutrons.
Generally, the isotopes of a chemical element have the same chemical properties because of their atomic number but different physical properties due to their atomic weight (mass number).
Given the following data;
Relative abundance of Z-19 = 55%
Relative abundance of Z-21 = 45%
Atomic mass of Z-19 = 19 amu
Atomic mass of Z-21 = 21 amu
To find the average atomic mass;
Average atomic mass = 19 * (55/100) + 21 * (45/100)
Average atomic mass = 19*0.55 + 21*0.45
Average atomic mass = 10.45 + 9.45
Average atomic mass = 19.9 amu
Therefore, the average atomic mass for element Z is 19.9 amu.
Answer:
Mass of CO2 produced = 944.43 -lb/year
Since 944.43 -lb is close to 1000 -lb, it is a reasonable statement.
Explanation:
Assumptions:
Car mileage = 20 miles/gallon:
Density of gasoline = 0.702 g/ml
Volume of gallons per week = (20 miles/week) / (20 miles/gallon) = 1 gallon/week
Volume of gasoline per year = 52 weeks * 1 gallon/week = 52 gallons
1 gallon = 3.8 litres or 3800 ml
52 gallons = 52 * 3800 = 197600 ml
Mass of gasoline = volume *density
Mass of gasoline = 197600 ml * 0.702 g/ml
Mass of gasoline = 138715.2 g
Equation of reaction:
2C8H18 + 25O2 ---> 16CO2 + 18H2O
2 moles of octane produces 16 moles of CO2
Molar mass of octane = 114 g/mol; molar mass of CO2 = 44 g/mol
114 * 2 g of octane = 44 * 16 g of CO2
138715. 2 g of octane produces = (138715.2 * 44 * 16) / 114 * 2 of CO2
Mass of CO2 produced = 428313.6 g of CO2 = 428.3136 Kg
Mass of CO2 produced in -lb weight = 428.3136 * 2.205
Mass of CO2 produced per year = 944.43 -lb CO2
Since 944.43-lb is close to 1000 -lb, therefore, it is a reasonable statement.
Answer:
504.57 K.
Explanation:
From the question given above, the following data were obtained:
Number of mole (n) = 6.81 moles
Pressure (P) = 2.99 atm
Volume (V) = 94.35 L
Gas constant (R) = 0.0821 atm.L/Kmol
Temperature (T) =.?
Using the ideal gas equation, the temperature of the ideal gas can be obtained as follow:
PV = nRT
2.99 × 94.35 = 6.81 × 0.0821 × T
282.1065 = 0.559101 × T
Divide both side by 0.559101
T = 282.1065 / 0.559101
T = 504.57 K.
Thus, the temperature of the ideal gas is 504.57 K.
Answer:
Explanation:
Hello,
In this case, considering the required product which is dinitrogen tetroxide whose molecular formula is N₂O₄, by considering its formation reaction which is starting by both gaseous nitrogen and oxygen as shown below:
Nevertheless, it should be balance since four oxygen atoms are present at the right side, thus, we obtain:
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