Answer:
The molarity of the magnesium chloride solution is 1.47 mol/L.
Explanation:
Molarity is defined as number of moles of compounds present in a unit liter of volume of the solution
Moles of magnesium chloride = 6.90 moles
Volume of solution = 4.70 L
The molarity of the magnesium chloride solution is 1.47 mol/L.
Answer:
C. Water passes into the salt solution, dehydrating bacterial cells and making them harmless.
Explanation:
The salt solution is hypertonic to the bacterial cells and as such, water molecules will move from the bacterial cells into the salt solution, dehydrating the cells and rendering them harmless.
Option A is also true but it is irrelevant to the question asked. Option B and D are wrong.
The correct option is C.
Answer:
If a neutral atom has 22 protons inside its nucleus, it will have 22 electrons orbiting the nucleus.
Explanation:
An atom is the smallest amount of matter that undergoes chemical changes and is made up mainly of subatomic particles: electrons, protons and neutrons. The atomic nucleus is made up of protons, with a positive electric charge, and neutrons, which have no charge, while electrons, with a negative electric charge, revolve around the nucleus.
A neutral atom is one that lacks an electrical charge due to a trade-off between the number of its protons and electrons. In other words, although it has an electric charge, it is balanced between protons, electrons and neutrons. So in a neutral atom, the number of electrons equals the number of protons because the negative charge of the electrons is offset by the positive charge of the protons.
<u><em>If a neutral atom has 22 protons inside its nucleus, it will have 22 electrons orbiting the nucleus.</em></u>
72 percent is hydrogen. Nuclear fusion converts hydrogen into other elements. The sun is also composed of about 26 percent helium and trace amounts of other elements; oxygen, carbon, neon, nitrogen, magnesium, iron and silicon.
http://www.space.com/17170-what-is-the-sun-made-of.html