Explanation:
This is due to a reduction in atmospheric pressure – pressure due to the weight of the overlying air column). Remember that the higher the altitude the lower the air density and subsequently the lower the air pressure.
Therefore when heating water at higher altitude the vapor pressure of the water at the surface overpowers the atmospheric pressure – which is slightly lower than at sea level – even before the water temperatures reach 100 degrees centigrade.
Answer:
Explanation: IE1 increases from left to right across a period. However, since Na has only one valence electron, IE2 for Na involves the removal of a core electron − requiring significantly more energy.
Answer:
AlF3
Explanation:
Aluminum fluoride is an inorganic compound of chemical formula AlF3. Such a compound originates from the treatment of aluminum hydroxide particles with hydrogen fluoride, which react and give rise to aluminum fluoride. This is a very important solid and crystalline element during the production of other compounds that use aluminum oxides because it has the ability to lower the melting point.
Nonrenewable natural resources are resources that cannot be replenished within a lifetime.
Answer:
12 mmilligrams of Po-218 was the mass of the original starting material
Explanation:
The half-life of a radioactive material is the time taken for half the amount ofnthe original material present in a radioactive material to decay or disintegrate.
After each half-life, half the original material present at the start remains.
For the radioactive polonium-218 having a half-life of 3.04 minutes, it means that if 1 g is the starting material, after 3.04 minutes, 1/2 g will be remaining; after, 6.08 minutes 1/2 of 1/2 which is 1/4 of the starting material will be remaining; and after 9.12 minutes, 1/2 of 1/4 = 1/8 g will be remaining.
From the question, number of half-lives undergone after 9.12 minutes = 9.12/3.04 = 3 half-lives.
After 3 half-lives, 1/8 of the original material is remaining.
1/8 = 1.50 mg
The original mass of the sample at the start = 1.50 mg × 8 = 12 mg
Therefore, 12 milligrams of Po-218 was the mass of the original starting material.
