Answer: 27 is A and 28 is C.
Explanation: I’ll explain 28 but not 27 because that’s just definitions.
In CuSO4 there is a Cu, an S, and 4 O molecules. Add them up you get 6.
The purpose of an universal indicator is to test wether a solution is acid or if its a base. It changes colors according to the PH's. It helps a lot in the indication of a chemical reaction because it can say if <span>each component loses or gains protons depending upon the acidity or basicity of the solution being tested.An universal indicator can say if a determined solution proves to be endothermic or exothermic. If the solution is not tested as acid or base then we cannot knwo if there will be an endothermic reaction or an exhotermic one</span>
The statement that best describes the trend in first ionization enery of elements on the periodic table is:
<span>It generally decreases down a group because valence electrons are farther from the nucleus.
The first ionization energy measures how difficult is to release an electron from the outermost shell. The higher the ionization energy the more difficult it is to release an electron, the lower the ionication energy the easier to release an electron.
As the atomic number of the atom increases (which is what happens when you go down a group) the furthest the outermost shell of electrons will be (the size of the atoms increases) and so those electrons require less energy to be released, which means that the ionization energy decreases.
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Answer:
Single-Replacement Reaction
General Formulas and Concepts:
<u>Chemistry - Reactions</u>
- Synthesis Reactions: A + B → AB
- Decomposition Reactions: AB → A + B
- Single-Replacement Reactions: A + BC → AB + C
- Double-Replacement Reactions: AB + CD → AD + BC
Explanation:
<u>Step 1: Define RxN</u>
Mg + H₂SO₄ → MgSO₄ + H₂
<u>Step 2: Identify RxN</u>
Mg + H₂SO₄ → MgSO₄ + H₂
Single-Replacement Reaction A + BC → AB + C
- A = Mg
- BC = H₂SO₄
- AB = MgSO₄
- C = H₂
Answer:
Ammonia is the richest source of nitrogen on a mass percentage basis because it has 82.35% of nitrogen by mass.
Explanation:
Percentage of element in compound :
(a) Urea, 
Molar mass of urea = 60 g/mol
Atomic mass of nitrogen = 14 g/mol
Number of nitrogen atoms = 2
(b) Ammonium nitrate, 
Molar mass of ammonium nitrate = 80 g/mol
Atomic mass of nitrogen = 14 g/mol
Number of nitrogen atoms = 2
(c) Nitric oxide, NO
Molar mass of nitric oxide = 30 g/mol
Atomic mass of nitrogen = 14 g/mol
Number of nitrogen atoms = 1
(d) Ammonia, 
Molar mass of ammona = 17 g/mol
Atomic mass of nitrogen = 14 g/mol
Number of nitrogen atoms = 1
Ammonia is the richest source of nitrogen on a mass percentage basis because it has 82.35% of nitrogen by mass.
