Which of the following is a radioisotope used to date rock formations older than 50,000 years old?
a) carbon-12
b) uranium-235
c) cobalt-60
d) carbon-14
any is appreciated : )

Darla claims that the first periodic table developed by mendeleev was not completely accurate, so it is not useful at all. harmony argues that it establish the periodic table we use today, making it more credible. who is correct and why? darla is correct, because a model that has any mistakes should be thrown out. darla is correct, because a good model would not need to change. harmony is correct, because mendeleev’s model had all of the information correct in the first version. harmony is correct, because mendeleev’s model made predictions that came true.

How do i turn 2 s into one in the products

State one important difference between a physical change and a chemical change?