Calculate the food energy (joules/g) of one of your food
samples. one chemistry calorie is equal to 4.186 joules. convert the energy you
calculated to kilojoules (1 kj = 1000 j). since nothing is given, an example is
avocadoes have 160 cal/100 g serving
(160 cal/ 100 g)(4.186 J/ 1 cal) (1 kJ/1000 J) = 0.0067 kJ/g
Molar mass is the mass of 1 mol of substance.
Molar masses of compounds can be calculated by the sum of the products of molar masses of individual atoms by number of corresponding individual atoms.
Compound formula is C₉H₈O₄
the molar masses of the atoms making up the compound
C - 12 g/mol x 9 C = 108
H - 1 g/mol x 8 H = 8
O - 16 g/mol x 4 O = 64
therefore molar mass of aspirin = 108 + 8 + 64 = 180 g/mol
answer is 3.180
Answer:
P = 2.145kPa
Explanation:
Mass = 22.1g
Molar mass of CO2 = 44g/mol
Vol = 165mL = 0.165L
T = -188°C = (-188 + 273.15)K = 85.15K
R = 8.314J/mol.K
From ideal gas equation,
PV = nRT
P = pressure of the ideal gas
V = volume the gas occupies
n = number of moles if the gas
R = ideal gas constant
T = temperature of the gas
n = number of moles
n = mass / molar mass
n = 22.1 / 44 = 0.50moles
PV = nRT
P = nRT/ V
P = (0.5 × 8.314 × 85.15) / 0.165
P = 2145.26Pa = 2.145kPa
Pressure of the gas is 2.145kPa
Answer:
3
Explanation:
Applying,
= R/R'............... Equation 1
Where n' = number of halflives that have passed, R = Original atom of the substance, R' = atom of the substance left after decay.
From the question,
Given: R = 40 atoms, R' = 5 atoms
Substitute these values into equation 1
= 40/5
= 8
= 2³
Equation the base,
n' = 3
