Because the modern periodic table is according to icnreasing atomic numbers.Ar has the atomic number 18 and potassium 19 so Argron is placed before K in the Modern periodic table.
Answer:
4 elements for C7H5(NO2)3
This question is dealing with the half-life of carbon-14 which can be used to determine the age of a substance according to the following equation:
t = [ln(N/No)/(-ln2)] · t1/2
N = # of carbon-14 atoms presently = 250 atoms
No = # of carbon-14 atoms initially = 1000 atoms
t1/2 = half-life = 5730 years for carbon-14
We can now input all of the information into the formula to find the age of the fossil:
t = [ln (250/1000)/-ln2] x 5730 years
t = 11460 years
The fossil should be found to be roughly 11,460 years old.
<u>Answer:</u> The correct answer is Option C.
<u>Explanation:</u>
Net ionic equation of any reaction does not include any spectator ions.
Spectator ions are defined as the ions which does not get involved in a chemical equation. They are found on both the sides of the chemical reaction when it is present in ionic form.
The chemical equation for the reaction of sodium bicarbonate and acetic acid is given as:

Ionic form of the above equation follows:

As, sodium and acetate ions are present on both the sides of the reaction. Thus, it will not be present in the net ionic equation and are spectator ions.
The net ionic equation for the above reaction follows:

Hence, the correct answer is Option C.
H₂SO₄ + 2NH₄OH → (NH₄)₂SO₄ + 2H₂O
Explanation:
Unbalanced reaction equation:
H₂SO₄ + NH₄OH → (NH₄)₂SO₄ + H₂O
We can use a simple mathematical approach to balance this equation by solving simple algebraic equations.
aH₂SO₄ + bNH₄OH → c(NH₄)₂SO₄ + dH₂O
a,b,c and d are simple coefficients that will balance the equation:
Conservation of H: 2a + 5b = 8c + 2d
S: a = c
O: 4a + b = 4c + d
N: b = 2c
lets assume that a = 1
c= 1
b = 2
Solving for d from 4a + b = 4c + d
d = 4a + b -4c = 4(1) + 2 - 4(1) = 2
H₂SO₄ + 2NH₄OH → (NH₄)₂SO₄ + 2H₂O
Learn more:
Balancing of equations brainly.com/question/6078553
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