25.13(5512)
4568%of the time is 56789
5678
4333
Answer:
a pencil being sharpened
freezing water
boiling water
Explanation:
a physical change doesn't change the chemical structure of an object. That is why the other 2 are wrong
Answer: 66
Explanation: To find the mass number you would have to add the number of protons and the number of neutrons.
Answer:
B. 0.2.
Explanation:
<em>n = mass/molar mass</em>
mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.
<em>∴ n = mass/molar mass = </em>(20 g)/(100.0869 g/mol) <em>= 0.1998 ≅ 0.2 mol.</em>
<em></em>
<em>So, the right choice is: B. 0.2.</em>
Its charge would be the amount of electrons that are lost in total, which the information is not stated
