Answer:
Half life is the time taken by a radio active isotope to reduce by half of its original amount. Radium-226 has a half life of 1602 years meaning that it would take 1602 years for a mass of radium to reduce by half.
Number of half lives in 9612 years = 9612/1602 = 6 half lives
New mass = Original mass x (1/2)n where n is the number of half lives.
Therefore, New mass= 500 x (1/2)∧6
= 500 x 0.015625
= 7.8125 g
Hence the mass of radium after 9612 years will be 7.8125 grams.
Explanation:
Answer:
54g
Explanation:
Given parameters:
Number of moles of H₂O = 3 moles
Unknown:
mass of water = ?
Solution:
To solve this problem, we use the expression below:
mass = number of moles x molar mass
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Mass of water = 3 x 18 = 54g
Uses of nonmetals in our daily life: Oxygen which is 21% by volume helps in the respiration process.
Nonmetals used in fertilizers: Fertilizers contain nitrogen.
Nonmetals used in crackers: Sulphur and phosphorus are used in fireworks.
The last row going across
Answer:
See the answer below, please.
Explanation:
Take as an example a light bulb inside a lamp to illuminate a room. When you plug it in a plug and turn it on, light is generated. More precisely, heat (Joule effect) is produced inside the lamp by its internal filament (conductive material) when it passes through the electrical energy, generated by the friction of the atoms that are inside it when it encounters a resistance.
