Answer:
analytic chemistry
Explanation:
Analytical chemistry uses tests to discover ingredients in a substance. A pool worker tests the water to learn how much chlorine it contains. A nutritionist analyzes food to learn about the nutrients in it. Biochemistry is the study of chemistry in the body.
Answer:

Explanation:
First, we need to find the molecular mass of water (H₂O).
H₂O has:
- 2 Hydrogen atoms (subscript of 2)
- 1 Oxygen atom (implied subscript of 1)
Use the Periodic Table to find the mass of hydrogen and oxygen. Then, multiply by the number of atoms of the element.
- Hydrogen: 1.0079 g/mol
- Oxygen: 15.9994 g/mol
There are 2 hydrogen atoms, so multiply the mass by 2.
- 2 Hydrogen: (1.0079 g/mol)(2)= 2.0158 g/mol
Now, find the mass of H₂O. Add the mass of 2 hydrogen atoms and 1 oxygen atom.
- 2.0158 g/mol + 15.9994 g/mol = 18.0152 g/mol
Next, find the amount of moles using the molecular mass we just calculated. Set up a ratio.

Multiply. The grams of H₂O will cancel out.



The original measurement given had two significant figures (3,2). We must round to have 2 significant figures. All the zeroes before the 1 are not significant. So, round to the ten thousandth.
The 7 in the hundred thousandth place tells us to round up.

There are about <u>0.0018 moles in 0.032 grams.</u>
The answer is (4) Ag(s)
Solid Silver has a Face Centered Cubic crystal structure.
The remaining choices are gases (H2 & Ar) and liquid (Br). Liquids and gases do not form crystal structures as their atoms are loose.
Answer:
May i ask what is the question?
Explanation:
Answer:
Because only a few bacterias can "fix" the atmosphere nitrogen.
Explanation:
The nitrogen at the atmosphere is in the form of N₂ and represents 78% of the atmosphere composition. The element is part of the constitution of nucleic acids and proteins, so the living beings needed them.
However, the animals and the plants can't catch the N₂. Some bacterias that live in mutualism with plants have this ability, and they "fix" the atmosphere nitrogen, transforming the N₂ in the ions nitrite (NO₃⁻) or ammonia (NH₃), which can be caught by the plants.
Them, when the primary consumers eat the plants they catch the nitrogen, which will be passed through the food chain.
So, it's difficult to pull nitrogen from the atmosphere into the nitrogen cycle of the biosphere because only a few bacterias can do it.