Answer:
Charge the balloon, hold it near an electroscope, and determine if the electroscope leaves move.
Explanation:
The gold leaf electroscope is an instrument used to detect if a body is charged. It has two gold leafs suspended from a brass stem in a vacuumed glass jar and connected to a metal cap(Toppr).
When the test body is allowed to touch the metal cap, a change in the size of the leaves shows whether the body is charged or not.
Since we are suspecting the balloon to be made up of a metal; metals can be charged. We can test if there is really a charge on the balloon by bringing it near an electroscope to see if the electroscope moves.
Answer:
One
Explanation:
An element is a pure substance in which there are only one kind of atom. Elements are distinct substances that cannot be split up into simpler substances.
Such substances consists of only one kind of atom. There are over a hundred known elements to date.
Generally, as a pure substance, the composition of an element is definite and they are homogenous in all parts.
Answer: the answer should and most definitely be D.
Explanation: I mean think about it after a while only a few radioactive nuclei are left which means it will dye down after a while which also makes it very boring hope this helps :)
Answer:
The catalyzed reaction will take 2.85 seconds to occur.
Explanation:
The activation energy of a reaction is given by:

For the reaction without catalyst we have:
(1)
And for the reaction with the catalyst:
(2)
Assuming that frequency factor (A) and the temperature (T) are constant, by dividing equation (1) with equation (2) we have:

Since the reaction rate is related to the time as follow:
![k = \frac{\Delta [R]}{t}](https://tex.z-dn.net/?f=%20k%20%3D%20%5Cfrac%7B%5CDelta%20%5BR%5D%7D%7Bt%7D%20)
And assuming that the initial concentrations ([R]) are the same, we have:
![\frac{k_{1}}{k_{2}} = \frac{\Delta [R]/t_{1}}{\Delta [R]/t_{2}}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bk_%7B1%7D%7D%7Bk_%7B2%7D%7D%20%3D%20%5Cfrac%7B%5CDelta%20%5BR%5D%2Ft_%7B1%7D%7D%7B%5CDelta%20%5BR%5D%2Ft_%7B2%7D%7D%20)


Therefore, the catalyzed reaction will take 2.85 seconds to occur.
I hope it helps you!