Answer:
A. Producing certain synthetic materials could have a greater environmental impact than disposing of them.
Explanation
I just did this question and got it right.
Explanation:
Hi for this one u just need to remember and use the equation.

then u find mr of potassium which is 39.1.
then u do

you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .
hope this helps :)
Answer:
The expression will be T=7r
Explanation:
From equation S=dT/dr, we can solve this equation by integrating it and usig the values 25C and 18C for T and 2 and 1 for the radius. The solution to the integration will result in the value for S. For this example, it will be 7. Therefore, the main expression will be T= 7r in which the temperature is in fuction of the radius between the spheres.
Answer: 1and 4
Explanation: iron is an element not an alloy. An ionic lattice is not bonded covalently.