Answer:
Because it can cause health problems or injuries to our sense organs.
Explanation:
Chemicals in the laboratory are made up of different constituents, which may be dangerous or injurious to health. This is the reason why safety measures or precautions have to be taken when working in the laboratory. One of those safety measures is that "one should never use taste, touch, or smell to identify an unknown chemical".
This is so because a chemical that is unknown amounts to the fact that what such chemical contains is unknown, hence, the chemical might have the ability to cause harm or injuries to the sense organ. For example, a conc. acid that is tasted will burn the tongue etc.
Answer:
The correct option is: c. 15
Explanation:
Phosphorous is a chemical element which belongs to the group 15 of the periodic table and has atomic number 15. It is a highly reactive non-metal of the p-group.
Since, atomic number of an atom is the number of electrons and number of protons for neutral atoms.
So, the number of protons = number of electrons = 15
The atomic mass is obtained by adding the number of neutrons and the protons.
So, number of neutrons + number of protons = 30
So, number of neutrons + 15 = 30
Therefore, the number of neutrons in ³⁰P = 15
25° C is the temperature required for the cell potential to be the standard cell potential
Answer:
C₆H₆
Explanation:
Molar mass of the compound is 78g/mol
Unknown:
Molecular formula of the compound = ?
Solution:
The empirical formula of the compound is CH.
Empirical formula is the simplest formula of a compound.
To solve this problem:
Find the molar mass of CH;
Molar mass = 12 + 1 = 13g/mol
Multiplication index = 
= 6
So;
(CH)₆ ;
Therefore:
C₆H₆
