Answer:
The answer is in the problem
Explanation:
As general rule of number of oxygen is -2:
O → -2
Alkali metals (Li, Na, K) are always +1
Na → +1
Alkali earth methals (Be, Mg, Ca...) are always +2
Ca → +2
The halogen group (F, Cl, Br...) is always -1
F → -1
The oxidation number of Si (+/- 4)
Aluminium is, usually +3
And to complete the octet rule in nitrogen, 3 electrons are required. That means:
N → -3
I believe it is that most oxides are solids other than these three. i hope this helps.
Isotopes of an element will contain the same number of protons and electrons but will differ in the number of neutrons they contain. In other words, isotopes have the same atomic number because they are the same element but have a different atomic mass because they contain a different number of neutrons.
Answer:
Sodium iodide NaI
Magnesium chloride MgCl₂
Explanation:
Silicon dioxide SiO₂ it is not soluble in water, so it can not be recrystallized from water, it is a white solid and the boiling point is 2230 °C. This one is not the unknown solid.
Sodium iodide NaI it is soluble in water, it has a white color and the boiling point is 1304 °C
. This can be the unknown solid.
Magnesium chloride MgCl₂ is soluble in water, it have a white color and the boiling point is 1,412 °C
. This can be the unknown solid.
Phosphorus tribromide PBr₃ is will start a hydrolysis reaction in water, it is a colorless liquid and it has a boiling point of 173 °C. This one is not the unknown solid.