Answer:
- <u><em>3.30 × 10³ years</em></u>
Explanation:
1) <u>Carbon-14 disintegration rate of a young (alive) tree</u>: 0.266 per second per gram.
2)<u> Carbon-14 disintegration rate of a wood sample prepeared from an object recovered at an archaelogical excavation (dead matter):</u> 0.178 per second per gram.
3) <u>Ratio of decay</u>: A/A₀ = 0.178 / 0.266 = 0.669
4) <u>Half-life equation</u>: A/A₀ = (1/2)ⁿ, where n is the number of half-lives since the object died.
5) <u>Substitute and solve for n</u>:
That means that 0.578 half-life has elapsed since the wood with which the object was created was dead matter.
6) <u>Convert number of half-lives to years</u>:
- 0.578 half-life × 5715 years/half-life = 3,303 years = 3.30 × 10³ years.
The chemical composition of water is H2O – two hydrogen atoms and one oxygen atom. Water has special properties because of the way these atoms bond together to form a water molecule, and the way the molecules interact with each other. ... Water's polarity allows it to dissolve other polar substances very easily.
<u>Given:</u>
Pressure = 565 torr
<u>To determine:</u>
Corresponding pressure in atmospheres
<u>Explanation:</u>
Pressure is commonly expressed in units like:
Atmosphere (atm), Torr or mmHg
The SI unit is atm, where
760 torr = 1 atm
Thus, a pressure reading of 565 torr corresponds to:
565 torr * 1 atm/760 torr = 0.743 atm
They work by lowering the activation energy
Answer:
Solid state : In this state, the molecules are arranged in regular and repeating pattern. The molecules are closely packed that means they are fixed and vibrate in place but they can not move from one place to another. They have least kinetic energy. For example : chair
Liquid state : In this state, the molecules are present in random and irregular pattern. The molecules are closely packed but they can move from one place to another. They have more kinetic energy than solids but less than that of gases. For example : oil
Gaseous state : In this state, the molecules are present in irregular pattern. The molecules are not closely packed and they can move freely from one place to another and spread out. They have most kinetic energy. For example : Hydrogen
