Answer:
Boiling water breaks intermolecular attractions and electrolysis breaks covalent bonds.
Explanation:
When water boils, hydrogen bonds are broken between adjacent water molecules. The hydrogen bond is an intermolecular bond between adjacent oxygen and hydrogen atoms of water molecules.
During electrolysis, water dissociates in the presence of electric current. Here, ions are formed in the process. Therefore, covalent bonds are broken here.
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
Explanation:
1) Atoms can not be subdivided. It has been changed as it is possible to divide an atom into Protons, Neutrons and Electrons as well as other smaller particles.
2) The regulations for the chemical mixture have always been altered to the rules for the chemical combination in the creation of organic compounds may be denied.
3)Atoms are of a particular element are identical in all respects i. e. they have same mass and similar properties.
It was modified. And according. to new search;
Atoms of the same element may not be always identical.
Answer:
zince chloride will be formed and hydrogen gas will be librated.
Explanation:
When dilute HCl is added to zinc pieces, a rection will takes place as follows :
It means that zinc chloride will form when zinc reacts with dilute HCL. Also hydrogen gas will produced.
As zinc is more reactive than hydrogen, it displaces hydrogen from its solution and forms zinc chloride. The form product is white in color and H₂ is an odorless gas.
Hence, zince chloride will be formed and hydrogen gas will be librated.
Answer: (C) Although the average kinetic energy of the colliding substances increases, this has no influence on activation energy.
Explanation:
After increasing the temperature of the reaction , the rate of the chemical reaction increases due to increase in the average kinetic energy of the particles. At increased temperature high proportions of particles can react making the reaction faster.
