Answer:
112.22 g
Explanation:
mass = no. of moles x atomic mass
From the periodic table, we can see the atomic mass of Ca is 40.078.
Therefore,
mass = 2.80 x 40.078
= 112.22g (corrected to 2 decimal places.)
Don't you think that element is ferrous i mean iron.
The formula Ca(ClO3)2 breaks down to: 1 calcium atom, 2 chlorine atoms, and 6 oxygen atoms. Therefore:
One molecule of calcium chlorate contains 9 atoms [correct]
Calcium chlorate is not an element, nor does the molecule contain only 3 atoms [incorrect]
It does not take 9 different elements - just the three elements we listed [incorrect]
Calcium chloride only contains one Ca group [incorrect]
<u>Answer 2 :</u> The given electronic configuration for a neutral atom of phosphorous in its ground state is incorrect.
Explanation :
A neutral atom of phosphorous has 15 electrons.
The given electronic configuration is incorrect.
The reason is, According to Aufbau principle, the electrons will be first filled in the sub-shell having lower orbital energy. As from the given configuration, 3p sub-shell has lower orbital energy than 4s sub-shell. So, the electrons will be filled in 3p sub-shell first. Hence, the ground state electronic configuration of neutral atom of phosphorous is,

<u>Answer 3 :</u>
Element Rubidium Magnesium Aluminium
Symbol Rb Mg Al
Group number 1 2 13
Number of valence 1 2 3
electrons
The order of general reactivity on the basis of number of valence electrons.
Rb > Mg > Al
Reason : The reactivity is determined by the number of electrons present in the outermost shell that means the element which have 1 valence electron will be more reactive because they can easily lose electrons.