<u>Answer:</u> The equation to calculate the mass of remaining isotope is ![[A]=\frac{20}{10^{-0.217t}}](https://tex.z-dn.net/?f=%5BA%5D%3D%5Cfrac%7B20%7D%7B10%5E%7B-0.217t%7D%7D)
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:

where,
= half life of the reaction = 
Putting values in above equation, we get:

Rate law expression for first order kinetics is given by the equation:
![k=\frac{2.303}{t}\log\frac{[A_o]}{[A]}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B%5BA_o%5D%7D%7B%5BA%5D%7D)
where,
k = rate constant = 
t = time taken for decay process
= initial amount of the sample = 20 grams
[A] = amount left after decay process = ? grams
Putting values in above equation, we get:
![0.5=\frac{2.303}{t}\log\frac{20}{[A]}](https://tex.z-dn.net/?f=0.5%3D%5Cfrac%7B2.303%7D%7Bt%7D%5Clog%5Cfrac%7B20%7D%7B%5BA%5D%7D)
![[A]=\frac{20}{10^{-0.217t}}](https://tex.z-dn.net/?f=%5BA%5D%3D%5Cfrac%7B20%7D%7B10%5E%7B-0.217t%7D%7D)
Hence, the equation to calculate the mass of remaining isotope is ![[A]=\frac{20}{10^{-0.217t}}](https://tex.z-dn.net/?f=%5BA%5D%3D%5Cfrac%7B20%7D%7B10%5E%7B-0.217t%7D%7D)
The correct answer is - 1 cm/yr.
Alongside the western coast of South America, the Nazca plate and the South American plate are in a collision for several million years now, with the Nazca plate being the one that is subducting in this convergent plate boundary.
If the Nazca plate's focus has moved 1,000 km in the last 10 million years, than in order to get to the annual movement of the subduction we need to convert the km into cm first:
1 km = 10,000 cm
1,000 x 10,000 = 10,000,000
1,000 km = 10,000,000 cm
Than we need to divide the number of cm with the number of years:
10,000,000 / 10,000,000 = 1
And we get the result of 1 cm/yr.
Answer:
2.At a given temperature, the KE of all gases is the same.KE depends only on Kelvin temperature
Explanation:
The kinetic molecular theory of gases provides a succint expalantion and insight into the behaviour of gases. The assumptions of the theory are stated below:
- Gases are made up of large number of identical molecules which are moving at different speeds.
- Spaces occupied by molecules of gases are negligible compared to the volume of the container.
- Molecules of gases are independent of one another.
- The molecules collide with themselves and the walls of the container elastically.
- The temperature of a gas is a measure of only the average kinetic energy of the molecules.
An alligator has has an extra eyelid that protects there eyes underwater. It's basically their own built-in goggles.