They should identify the confounding variable.
Some condition that is not examined by the scientist might alter the experiment result. That condition is called confounding variable. If the method of the experiment same but result is very different, there should be unidentified confounding variable. It could be air humidity, temperature, ventilation, light, time of the year or anything that might not be seen by naked eye.
Try to redo the experiment with controlling variable as much as possible.
The answer is A hope this help
Metals :-
Group 1A - Alkali metals ( highly reactive metals)
Non-metals :-
Group 17 - Halogens ( highly reactive non-metals )
Answer:
Noble Gases are very stable because...
1) Noble Gases have a full octet
2) Low chemical reactivity
Explanation:
This means that is has 8 valence electrons so it won't need any more, so it is less likely to react with other substances.
Answer:
There will be one Al3+ ion.
There will be 3 NO3- ions
Explanation:
Dissociation equation:
Al(NO₃)₃ → Al³⁺ + 3NO₃¹⁻
When aluminium nitrate dissociate it produces one silver ion (Al³⁺) and three (NO₃¹⁻) ions.
Properties of Al(NO₃)₃:
It is inorganic compound having molecular mass 169.87 g/mol.
It is white odor less compound.
Its density is 4.35 g/mL.
Its melting and boiling points are 120°C and 440°C.
It is soluble in water.
It is sued to treat infections.
It is used in the photographic films.
It s toxic and must be handled with great care.
