Quick Lab Where's the Energy?

1.Obtain a flashlight and remove the batteries.
2. Turn the flashlight's switch on. Observe what happens.
3. Now put the batteries back in the flashlight, and turn the flashlight on. Observe what happens now.
4. Leave the flashlight turned on. After a few minutes, put your hand close to the bulb of the flashlight. What do you feel? Analyze and Conclude

1). Infer When the flashlight did not have batteries, what hap- pened when you switched it on? Why did this happen?

2). Relate Cause and Effect After you inserted the batteries into the flashlight, what happened when you turned the switch on? Why?

3). Apply Concepts What form of energy lights a flashlight bulb?

4). Use Analogies How is a flashlight battery like a box in which you put baseball bats when they are not being used?​

part 1: the half-life of the element is 22 years.

part 2: it will take 132.02 year for the sample to decay from 308.0 g to 4.8125 g.

explanation:

part 1: there are two ways to determine the half life time.

first way: the half life time can be determined directly from its definition as it is the time required for the sample to decay to its half concentration.

from the data the initial concentration was 45.0 g and decayed to its half value (22.5 g) in 22.0 years.

second way: the radio active decay is considered first order reaction so we can use the laws of first order reactions.

k = (1/t) ln (a/a-x), where k is the rate constant of the reaction,

t is the time of the reaction

a is the initial concentration of the reactant

a-x is the remaining concentration at time (t)

a = 45.0 g the initial concentration at t = 0 year.

at t = 22 year, a-x = 22.5 g

then k = (1/22 year) ln (45.0 g/ 22.5 g) = 0.0315 year-1.

the half-life time (t1/2) = ln 2/ k = 0.693/ k =0.693/ 0.0315 = 22 years.

part 2:

using the same law k = (1/t) ln (a/a-x),

using the given data; a = 308.0 g and a-x = 4.8125 g and the calculated k from the part 1 (k = 0.0315 year-1)

t = (1/k) ln (a/a-x) = (1/0.0315) ln (308.0/ 4.8125) = 132.02 years

i have no clue hope you find the answer

because natural gas is colorless, odorless, and tasteless, distributors add mercaptan (a chemical that smells like sulfur) to give natural gas a distinct unpleasant odor (it smells like rotten eggs). they locate the types of rock that are likely to contain natural gas deposits.

so she was walking and she stepped on warm jeffy , uh uh uhh dadye i just pooped my pants