Answer:
Sodium Hydroxide turns blue litmus red .
Answer:
Explanation:
The atomic number (Z) of copper is 29 and this isotope has an atomic mass (A) of 70.
The general symbol for an isotope E is 
.
The atomic number is a left subscript, and the atomic mass is a left superscript.
<span>This is a physical property. Physical properties involve changes of phase, or state of matter, of which melting is an example. Melting involves a change from a solid state to a liquid state. The internal energy of the solid increases, usually by applying heat, which increases the temperature to the melting point of the substance.</span>
I suggest watching Martin Shkerli YouTube channel. He has a ton of videos on chemistry and is very helpful.
