Answer:
2x+3y=-6
4x+3y=12
3x-y=5
5x+3y=1
Explanation:
standard form: ax + by = C
A chemical formula shows the kinds and numbers of <u>atoms</u> in the smallest representative unit of a substance.
<u>Explanation:</u>
In chemistry, a formula unit is the empirical formula of "ionic or covalent network solid compound" that is used as an independent entity for "stoichiometric calculations". This formula is a representation of a molecule that uses chemical symbols.
The unit is the lowest whole number ratio of ions represented in an ionic compound. It gives the numbers of atoms representing the "smallest representative" unit of a substance. The number of atoms also tells us about the chemical and physical properties of the compound formed.
Answer:
B. 0.2.
Explanation:
<em>n = mass/molar mass</em>
mass of CaCO₃ = 20 g, molar mass of CaCO₃ = 100.0869 g/mol.
<em>∴ n = mass/molar mass = </em>(20 g)/(100.0869 g/mol) <em>= 0.1998 ≅ 0.2 mol.</em>
<em></em>
<em>So, the right choice is: B. 0.2.</em>
A cow's<span> digestive system is quite different from that of humans. </span>Cows eat grass, hay and other plant material that contain hard-to-digest<span> cellulose. To cope with this </span>they<span> have a large stomach with four compartments, with the largest being the rumen.</span>
A burning fossil fuels that produces energy
