Answer:
Clarity and precision - these names are unique with each creature having only one scientific name. Helps avoid confusion created by common names. 3. Universal recognition - scientific names are standardised and accepted universally
Explanation:
Answer:
(c) pH = -log [H^+]
Explanation:
pH defines the acidicity or basicity a solution.
pH also refers to hydrogen ion concentration and it is only applied to aqueous solution.
pH ranges from 0 to 14. A pH of 7 is neutral and a pH less than 7 is acidic while a pH higher than basic.
Explanation:
Elements that belong to same group contains same number of valence electrons. Hence, they tend to show similar chemical properties.
When we move across a period then number of electrons get added to the same shell. As a result, there will be no increase in size of elements.
Also, metals are the elements that belong to group 1, 2 and d-block elements are also known as metals. Metallic character of elements decreases when we move left to right in a periodic table.
As most reactive metals are placed on the left side of periodic table.
Since, size of elements increases on moving down the group. So, an element is able to easily lose its valence electrons because of less force of attraction between its nucleus and valence electrons.
As a result, there will be increase in reactivity of metals on moving down the group.
Thus, we can conclude that given sentences are as follows.
- Elements in the same group have the same number of valence electrons.
-
Elements in the same period have the same number of electron shells.
-
Metallic elements become less reactive as you move left to right in a period.
-
Metallic elements become more reactive as you move top to bottom in a group.
Answer:
if you are working with hazardous materials.
Explanation:
A properly operating and correctly used fume hood can reduce or eliminate exposure to volatile liquids, dusts, and mists. It is advisable to use a laboratory hood when working with all hazardous substances.
Answer: 45
Explanation:
Recall that mass number = number of protons + number of neutrons. Hence, the mass number of the atom
= 22 + 23
= 45
Furthermore, the atomic number is equal to the number of protons. Hence, since the number of protons is 22. the atom has an atomic number of 22
Thus, An atom that contains 22 protons,
23 neutrons, and 22 electrons would have a mass of approximately 45
