Answer:
molecular weight of NH3 or grams This compound is also known as Ammonia. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles NH3, or 17.03052 grams.
.90 dL is 90 mL because 1 dL is 100 mL
Answer:
2 moles of Substance B
Explanation:
Because 1 mole of any substance contains 6.02× 10²³ particles either atoms, molecules, ions or even electron(Avogardo Constant)
Therefore 12.04 × 10²³/ 6.02× 10²³ = 2 mole of Substance B
A. The radioactive decay equation is N = N0
where T is the
half-life (5730 years), N0 is the number of atoms at time t = 0 and
N is the number at time t.
Rewriting this as:
(N/N0) = 
Since N = (1/8) N0 and
substituting known values:
1/8 = 
Taking ln of both
sides:
ln(1/8)= -ln(2)*t/5730
t = - 5730 * ln(1/8) /
ln (2)
t = 17,190 years
The tree was cut down 17,190
years ago.
B. N0 = 1,500,000 carbon-14 atoms
Since N = (1/8) N0
N = 187,500 carbon
atoms left