Answer:
There correct answer is option 1 (-50100 J)
Explanation:
Step 1: Data given
Mass of water = 150.0 grams
ΔHfus = 334 J/g
Temperature = 0°C
ΔHfus = the amount of energy needed to change phase of 1 mol water to ice
Step 2: Calculate the amount of heat required
Q = m*ΔHfus
⇒Q = the amount of heat reuired = TO BE DETERMINED
⇒m =the mass of water = 150.0 grams
⇒ΔHfus = 334 J/g
Q = 150.0 grams * 334 J/g
Q = 50100 J of heat required
Step 3: Calculate heat released
Qrequired = -Q released
Qreleased = -50100 J
There correct answer is option 1 (-50100 J)
Answer:
6 days
Explanation:
The following data were obtained from the question:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Half life (t½) =?
Next, we shall determine the decay constant. This can be obtained as follow:
Original amount (N₀) = 100 mg
Amount remaining (N) = 6. 25 mg
Time (t) = 24 days
Decay constant (K) =?
Log (N₀/N) = kt / 2.303
Log (100/6.25) = k × 24 / 2.303
Log 16 = k × 24 / 2.303
1.2041 = k × 24 / 2.303
Cross multiply
k × 24 = 1.2041 × 2.303
Divide both side by 24
K = (1.2041 × 2.303) / 24
K = 0.1155 /day
Finally, we shall determine the half-life of the isotope as follow:
Decay constant (K) = 0.1155 /day
Half life (t½) =?
t½ = 0.693 / K
t½ = 0.693 / 0.1155
t½ = 6 days
Therefore, the half-life of the isotope is 6 days
This is simple you need to expermient multyplul times
Sulfur atom= number of moles of the compound * number of sulfur atoms * Avogadro’s numbers
So it’s
4.6*1*6.022*10^23