Answer:
The mass number of an atom is equal to the number of protons plus the number of neutrons that it contains. In other words, the number of neutrons in an atom is its mass number minus its atomic number.
Explanation:
protons
The mass number of an atom is its total number of protons and neutrons. Atoms of different elements usually have different mass numbers , but they can be the same. For example, the mass number of argon atoms and calcium atoms can both be 40.
Answer:
1L
Explanation:
First, let us calculate the number of mole present in 20g of NaOH. This is illustrated below:
Mass = 20g
Molar Mass of NaOH = 23 + 16 + 1 = 40g/mol
Number of mole =?
Number of mole = Mass /Molar Mass
Number of mole of NaOH = 20/40 = 0.5mol
From the question given, we obtained the following data:
Molarity = 0.5M
Mole = 0.5mole
Volume =?
Molarity = mole /Volume
Volume = mole /Molarity
Volume = 0.5/0.5
Volume = 1L
A. Chloroplasts
B. The cell wall and the vacuole
C. Vacuoles
D. The mitochondrion
Silicon is the element having a mass of 28.09 g
<u>Explanation</u>:
- Silicon is the element having an atomic mass of 28.09 g / mol. So 28.09 g of silicon contains 6.023
10^23 atoms. One mole of each element can produce one mole of compound.
- The Atomic weight of an element can be determined by the number of protons and neutrons present in one atom of that element. So atomic weight expressed in grams always contain the same number of atoms( 6.023 10^23).
- Avagadro number is the number of atoms of 1 mole of any gas at standard temperature and pressure. It has been determined that 6.023 10^23 atoms of an element are equal to the average atomic mass of that element.
Answer:
Sources of air pollutants from the industry include: power generation plant, boilers, bleaching plants and caustic soda/chlorine plant. Pollutants include particulate matter, chlorine, sulfur dioxides, hydrogen sulfides, carbon dioxide, carbon monoxides and nitrous oxides.
