atoms are made of 3 types of sub atomic particles- protons, neutrons and electrons
from these 3 particles, electrons are responsible for participating in chemical bonds. therefore chemical properties of elements are based on the number of electrons present.
valence electrons are the number of electrons in the outermost energy shell that are involved in chemical bonds.
atoms with same number of valence electrons are grouped in to columns called groups.
therefore elements of the same group have same number of valence electrons, hence similar chemical properties.
from the options given
only Be and Mg belong to the same group they both belong to group 2 with 2 valence electrons
therefore Be and Mg have similar chemical properties
answer is
1) Be and Mg
Answer:
Tom is correct. The rate of reaction of Crystal violet and NaOH is first order with respect to NaOH, hence, a higher concentration of NaOH corresponds to a higher rate of reaction; a faster reaction.
This means the speed of cleaning depends on the concentration of the lye used.
Explanation:
The reaction between Crystal violet and NaOH, represented as
CV⁺ + OH⁻ → CVOH
It is a reaction that is know to turn the violet colour of the crystal violet colourless.
The rate of the reaction is also known to be second order; first order with respect to Crystal violet and first order with respect to NaOH.
This means that the rate of reaction is directly proportional to the concentration of NaOH provided all other parameters such as the rate constant and the concentration of Crystal violet are constant.
Hence, the reaction becomes faster with an increased concentration of NaOH.
So, Tom is right, concentrated lye solution would remove the stain faster.
Bob is wrong.
Hope this Helps!!!
Answer:
Percent Composition of 41K = 6.7302%
Explanation:
The explination is in the image.
D will because water just turns from liquid to a gas by adding heat. That is a physical change. The other equations are chemical changes.