Use blue litmus paper. This is an indicator that can safely determine whether it is a base or an acid by changing color in response to the substance. This color indicates whether it is an acid or a base. Refer to the pH scale to see if the substance is basic or acidic.
Answer: C. no new substances
are formed<span>
</span><span>
<span>In the
physical change of matter, there is no new substance that is formed. It is only
the appearance of the matter that is being changed and not its chemical
composition. Cutting, tearing and grinding are only some of the examples that
exhibit physical change. </span></span>
They are called hydrocarbons
B. False
It was created in 1869
Tc is Technetium, and it has an atomic number of 43. Its atomic configuration is [Kr] 5s(1) 4d(5) [I'm on my phone so I can't do numbers on shoulders, pretend that 1 and 5 are on the s and d's shoulder]
The outside most ring is the 4d(5), and the d orbital can hold ten electrons.
Valence electrons are electrons, in you could say the outside ring that isn't filled, the extra ones. In this case, there are 5.
