Answer:
Elements having same valence electrons are placed in <u>same group.</u>
Explanation:
First, let's start with some basic concepts of modern periodic table:
1. Modern Periodic table : It is the arrangement of element in the increasing order of their atomic numbers
The Modern periodic table is divided into Periods and groups .
Periods : These are the horizontal rows. There are seven periods in the periodic table . Period 1 has 2 element. Period two and three has 8 elements , period 4 and 5 have 18 elements and the period 6 and 7 have 32 elements.
Same period have same number of atomic orbital(Shell)
Group : The group is the vertical columns . There are 18 groups in the modern periodic table.Those element which have same group number will also have same number of electron in their outermost shell. The number of electron in the outermost shell determines the valency of the element.
So, elements showing same valency are placed in same group.
All alkali are place in group 1 and have 1 valance electron in the outermost shell
Answer: A: high ionization energies; high electron affinitlies.
Explanation: Covalent bonds are basically about sharing of electrons between two atoms to achieve that stable structure. They are formed between two atoms when both have similar tendencies to attract electrons to themselves (i.e., when both atoms have identical or fairly similar ionization energies and electron affinities). Covalent bonding usually occurs between two non-metals.
For effective and proper bonding, the two atoms involved in the covalent bonding exercise should be small and hungry for electrons. This is to enable the nuclei of both atoms to effectively attract and hold the shared electron(s) in place; hence, the need for high ionization energies & high electron affinities for a more effective covalent bonding.
Just dived both numbers by two
Answer:
Explanation:
2 moles hydrogen reacts with one mole of oxygen to give 2 moles of water.
a ) rate of consumption of hydrogen ( moles per second) is twice the rate of consumption of oxygen .
b ) rate of formation of water ( moles per second ) is twice the rate of consumption of oxygen
c ) rate of formation of water ( moles per second ) is equal to the rate of consumption of hydrogen.