The
half-life of this radioactive isotope is 9 months for it decreases to
one-fourth its original amount in 18 months. Half-life means a certain length
of time after which half of the amount of radioactive element has decayed.
Therefore,
the half-life of this particular isotope is 18 months. After 18 months the
isotope was at one-half, then another 18 months, the isotope was at one-fourth,
which is 9 months where one-fourth is one-half of one half.
Answer: 0.049 mol
Explanation:
1) Data:
n₁ = 0.250 mol
p₁ = 730 mmHg
p₂ = 1.15 atm
n₂ - n₁ = ?
2) Assumptions:
i) ideal gas equation: pV = nRT
ii) V and T constants.
3) Solution:
i) Since the temperature and the volume must be assumed constant, you can simplify the ideal gas equation into:
pV = nRT ⇒ p/n = RT/V ⇒ p/n = constant.
ii) Then p₁ / n₁ = p₂ / n₂
⇒ n₂ = p₂ n₁ / p₁
iii) n₂ = 1.15atm × 760 mmHg/atm × 0.250 mol / 730mmHg = 0.299 mol
iv) n₂ - n₁ = 0.299 mol - 0.250 mol = 0.049 mol
Answer:
I am going to guess it shows that the balloon is going downwards because the speed of rise is in the negatives for the last 2.
We know that a wave is a disturbance that transfers energy through matter or space There are two main types of waves: Mechanical and Electromagnetic. Water waves are mechanical. A mechanical wave is an oscillation of matter to transfers energy, but you always need a medium (substance such as: solid, liquid, gas, plasma) to transport it. The medium for water waves is, in fact, the water. For example, ripple in water is a surface wave. On the other hand, electromagnetic waves don't need a medium to transport, they can do it through the empty space. Then, this is the major characteristic that makes these two types of waves different.