A chemical process in which there is a gain of electrons is known as?
Sublimation
Reduction
Oxidation
Distillation
Correct answer is B
Reduction, any of a class of chemical reactions in which the number of electrons associated with an atom or a group of atoms is increased.
33
35
18
19
Correct answer is B
The Group 7 elements are called the halogens. They are placed in the vertical column, second from the right, in the periodic table .
Chlorine (17), bromine(35) and iodine(53) are the first three of the Group 7 elements.
The only metal that is anti-bacterial is?
Iron
Sodium
Alluminium
Copper
Correct answer is D
Aluminium sulfate is a salt soluble in water and is mainly used as a coagulating agent in the purification of drinking water.
Copper demonstrated the greatest antimicrobial activity. The silver coatings demonstrated the second most antimicrobial surface.
11.%
22.2%
10%
20%
Correct answer is C
Mass of Solution = Mass of Solute + Mass of Solvent → 20g + 180g
: Mass of Solution = 200g
Mass Percent = \(\frac{Mass of Solute}{Mass of Solution} * 100%\)
Mass percent = \(\frac{20}{200} * 100%\)
Mass percent = 10%
The nucleus of an atom consists of?
Electrons and neutrons
Electrons and protons
Protons and neutrons
None of the above
Correct answer is C
An atom nucleus is made up of protons and neutrons.
An electron is a negatively charged subatomic particle that orbits the nucleus of an atom.