Answer:
Explanation:
= Half-life of carbon = 5700 years
t = Time at which the remaining mass is to be found = 10400 years
= Initial mass of carbon = 11 g
Decay constant is given by
Amount of mass remaining is given by
The amount of the substance that remains after 10400 years is .
Answer:
A) 0.95 mol
Explanation:
We will assume the gas given off in the fermentation is an ideal gas because that allows us to use the ideal gas equation.
PV = nRT
First let's convert all measurements to units that we can use
P = 702 mmHg * 1 atm/760 mmHg = 0.92368 atm
V = 25.0 L
R = 0.08206 L-atm/mol-K
T = 22.5 °C +273.15 = 295.65 K
PV = nRT
0.92368 atm * 25.0 L = n * 0.08206 L-atm/mol-K * 295.65 K
n = 0.9518 mol
I don't understand the question
Can you elaborate further
Answer:
Explanation:
<u>1) First law of thermodynamic (energy balance)</u>
- Heat released by the the hot water (345K ) = Heat absorbedby the cold water (298 K) + Heat absorbed by the calorimeter
<u>2) Energy change of each substance:</u>
Heat released or absorbed = mass × Specific heat × change in temperature
- density of water: you may take 0.997 g/ ml as an average density for the water.
- mass of water: mass = density × volume = 50.0 ml × 0.997 g/ml = 49.9 g
- Specif heat of water: 1 cal / g°C
- Heat released by the hot water:
Heat₁ = 49.9 g × 1 cal / g°C × (345 K - 317 K) = 49.9 g × 1 cal / g°C × (28K)
- Heat absorbed by the cold water:
Heat₂ = 49.9 g × 1 cal / g°C × (317 K - 298 K) = 49.9 g × 1 cal / g°C × (19K)
- Heat absorbed by the calorimeter
Heat₃ = Ccal × (317 K - 298 K) = Ccal × (19K)
<u>4) Balance</u>
49.9 g × 1 cal / g°C × (28 K) = 49.9 g × 1 cal / g°C × (19 K) + Ccal × (19 K)
Ccal = [49.9 g × 1 cal / g°C × (28 K) - 49.9 g × 1 cal / g°C × (19 K) ] / 19K
Ccal = 23.6 cal/ K
- Convert to cal / K to Joule / K
23.6 cal / K × 4.18 J / cal = 98.6 J/K
Which rounded to 2 signficant figures leads to 99 J/k, which is the first choice.
Answer:
Size of the nucleus of an atom is very small as compared to the size of the atom.
According to Rutherford gold foil experiment, nucleus is very small in size as compared to the size of the atom as a whole. Nucleus is very hard, dense and positively charged which consists of protons and neutrons.
Explanation:
