An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire create a magnetic field which is concentrated in the hole, denoting the center of the coil
Proton: positive- mass equal to neutron
Electron: negative- mass 1/1840 mass of proton
Neutron: no charge- same mass as proton
Answer: There are
atoms of hydrogen are present in 40g of urea,
.
Explanation:
Given: Mass of urea = 40 g
Number of moles is the mass of substance divided by its molar mass.
First, moles of urea (molar mass = 60 g/mol) are calculated as follows.

According to the mole concept, 1 mole of every substance contains
atoms.
So, the number of atoms present in 0.67 moles are as follows.

In a molecule of urea there are 4 hydrogen atoms. Hence, number of hydrogen atoms present in 40 g of urea is as follows.

Thus, we can conclude that there are
atoms of hydrogen are present in 40g of urea,
.
Chlorine, Anthax is a biological agent, and uranium is a radioactive agent, and dynamite is just a no. Chlorine is a chemical gas.