Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
Whether water is frozen, in a gaseous state, or is a liquid, it is still H2O. So the chemical composition does stay the same.
Answer:
Oiling is done on a regular basis to sewing Machine because in the machine there are lots of machinery parts i.e. wheels and axels, etc. which are in continuous use and they possess so much frictional force between them that wear tear may be observed in those parts.
Yes, but they are tubular organs and like all other organs are made up of tissues
D. this is because they consume less resources, but produce just as much power. if this is wrong, which i doubt, it is a.
