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:
the velocity is 25 m/s
Explanation:
The computation of the velocity is shown below:
As we know that
Magnitude of Momentum = (mass) × (speed)
75 kg. m/s = 3 kg × speed
So, the speed is
= 75 ÷ 3
= 25 m/s
hence, the velocity is 25 m/s
Answer:
B
Explanation:
<h2>Soil is a mixture of </h2><h2 /><h2>tiny particles of rock,</h2>
<h2>dead plants and animals </h2>
<h2>,air and water.</h2>
Answer:
Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials. Incineration and other high-temperature waste treatment systems are described as "thermal treatment". Incineration of waste materials converts the waste into ash, flue gas and heat.
NOTE: The other person is drunk.
