Answer:
The correct answer is C. element
Explanation:
The sample cannot be an element because an element - or <em>elemental substance</em> - cannot be decomposed into simpler substances. Thus, it cannot be composed by differents types of atoms. For example, an element is carbon (C).
As the sample contains <u>three types of atoms</u>, it can be a compound, a molecule or a mixture, because they can be composed by different types of atoms - of different chemical elements. For example, the sample could contain the element carbon (C) combined with other elements, for example oxygen (O) or hydrogen (H), amoing others.
The first element discovered through synthesis was technetium<span>—its discovery being definitely confirmed in 1936. Hope that helps.</span>
Answer:
The answer to your question is 32.44 moles
Explanation:
Data
moles of Na₂CO₃ = ?
volume = 9.54 l
concentration = 3.4 M
Formula
Molarity = 
Solve for number of moles
number of moles = Molarity x volume
Substitution
Number of moles = (3.4)( 9.54)
Simplification
Number of moles = 32.44
1A: The legs can be a adjusted, as well as the sand can be swapped out. It’s a very good design for running multiple tests.
1B: He could add books or something under the front or back legs in order to increase/decrease the incline, therefore imitating the hypothesis.
1C: He can change out the sand grains to finer ones, or coarser ones, and record his results of each test.
2: If he sets the model at a steep incline and tests it with coarse sand and fine sand, seeing which one makes a narrower, deeper hole.
Answer:

Explanation:
Hello there!
In this case, according to the given chemical reaction:
2 Al + 3 Cl2 --> 2 AlCl3
Whereas there is a 2:3 mole ratio of aluminum to chlorine; it will be possible for us to calculate the required grams of aluminum by using the equality 22.4 L = 1 mol, the aforementioned mole ratio and the atomic mass of aluminum (27.0 g/mol) to obtain:

Regards!