Answer:
1 and 2
Explanation:
when we r adding chlorine to water
the water is clean
Answer:
Explanation:
Here we have to use stoichiometry.
First of all, we have to calculate the mass of 100% of yield:
1.7 g ------- 98%
X -------- 100%
X = 1.73 g (approximately)
Second, we have to calculate the mass of N2 that is necessary to react to produce the mass of 1.73g of NH3. To do that, we have to use the Molar mass of N2 and NH3 and don't forget the stoichiometric relationship between them.
Molar Mass N2 : 14x2 = 28 g/mol
Molar Mass NH3: 14 + 3 = 17 g/mol
28g (N2) ------- 17x2 (NH3)
X ------------ 1.73 g
X = 1.42 g (approximately)
Answer:
7.6 days
Explanation:
Radon is a radioactive element and Radon-222 is it's most stable isotope. The half-life of Radon-222 has been found to be approximately 3.8 days.
Let, the initial amount of the Rn-222 = 1 = A
Final amount =
= A'
We will use the following relation for calculating time elapsed in the decay

Thus,

We can write is as,

Since the base in both sides are equal, powers can also be equal and thus,

So, t = 7.6 days