Answer: (1)CaSO4 -> (2)O2 + (1)CaS
Explanation: edge 2020 chem
Answer : (C) Hafnium is the most likely identity of the given substance.
Solution : Given,
Mass of given substance (m) = 46.9 g
Volume of given substance (V) = 3.5 
First, find the Density of given substance.
Formula used :
Now,put all the values in this formula, we get
= 13.4 g/
So, we conclude that the density of given substance (13.4 g/) is approximately equal to the density of Mercury and Hafnium (13.53 and 13.31 g/ respectively).
According to the question the substance is solid at room temperature but Mercury is liquid at room temperature. So, Mercury is not identical to the given substance.
Another element i.e, Hafnium is the element whose density is approximately equal to the given substance and also solid at room temperature. And we know that the melting point of solid is high.
So, Hafnium is the most likely element which is the identity of the given substance.
The correct answer is higher melting point, bound by metal metal bonds.
While alkali metals only have one valence electron, alkaline earth metals have two. Metal to metal connections hold the metals together. Alkaline earth metals have a stronger metallic connection and a higher melting point because they have two valence electrons.
the characteristics that Group 2 metals excel in over Group 1 metals.
- Initial Ionization Potential
- Group 2 items are more difficult than group 1 elements.
- Strong propensity to produce bivalent compounds
As a result, group 2 metals have stronger metallic bonding, which leads to increased cohesive energy and compact atom packing. This explains why group 2 metals are harder and have higher melting and boiling temperatures than group 1 metals.
To learn more about Group 2A(2) refer the link:
brainly.com/question/9431096
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The haze is called smog, hope this helps, pls mark brainliest!
