We are given the following equation:
y = y0 e^-0.0001216 t
where y = 1/5 y0, y0 is the original amount
So solving for time t:
1/5 y0= y0 e^-0.0001216 t
t = 13,235.51 years
So the human died about 13235.5 years ago
Answer:
d) repeat
Explanation:
If the trend in a property is periodic, it means it will repeat on the periodic table.
Periodic properties on the table have a constant pattern as we move up or down a group or across a period from left to right.
- This helps to predict some of the salient properties of elements as we move through the periodic table.
- For example, on most periodic groups, metallicity increases as we move down the group and it decreases across the period.
Where is the chooses for you question
Answer:
V = 12.5 L
Explanation:
Given data:
Volume of NO = 15.0 L
Temperature and pressure = standard
Volume of nitrogen gas produced = ?
Solution:
Chemical equation:
6NO + 4NH₃ → 5N₂ + 6 H₂O
Number of moles of NO:
PV = nRT
n = PV/RT
n = 1 atm × 15.0 L / 0.0821 atm.L /mol.K × 273.15 K
n = 15.0 atm.L / 22.43 atm.L /mol
n = 0.67 mol
now we will compare the moles of No and nitrogen gas.
NO : N₂
6 : 5
0.67 : 5/6×0.67 = 0.56
Volume of nitrogen gas:
PV = nRT
1 atm × V = 0.56 mol × 0.0821 atm.L /mol.K × 273.15 K
V = 12.5 atm.L / 1 atm
V = 12.5 L