<span>It rises confidence for the reason that the more times you conduct the similar experiment over and over should either demonstrate your hypothesis right and wrong and remove any random incidences that might touch your results. Meaning it permits to have a more accurate measure or conclusion.</span>
Answer:
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Explanation:
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The Lewis structure of Chloroacetate (H₂CClCO₂) is given below. In structure it is shown that carbon has a double bond with one oxygen atom and two single bonds with CH₂Cl and O⁻.
Formal Charge; Formal charge is caculated as,
Formal charge = # of valence e⁻ - [# of lone pair of e⁻ + 1/2 # of bonded e⁻]
Formal charge on Oxygen (Highlighted Red);Formal charge = 6 - [ 6 + 2/2]
Formal charge = 6 - [6 + 1]
Formal charge = 6 - [7]
Formal charge = -1
Na⁺,SO₄²⁻ is the answer
<h3>Further explanation
</h3>
An ion is an atom or molecule that has a net electrical charge. There are many ions, one of them are sodium ion and sulfate ion.
SO₄²⁻ or Sulfate is a naturally occurring polyatomic ion that consist of a central sulfur atom surrounded by four oxygen atoms with occured widely in everyday life. Sodium ions are important for regulation of blood and body fluids, transmission of nerve impulses, heart activity, and certain metabolic functions.
Whereas Na⁺ or Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sulfate ion is a very weak base. Therefore sulfate ion undergoes negligible hydrolysis in aqueous solution.
Enter the symbol of a sodium ion, Na⁺, followed by the formula of a sulfate ion, SO₄²⁻. Separate the ions with a comma only—spaces are not allowed. Express your answers as ions separated by a comma. Therefore the answer is: Na⁺,SO₄²⁻
Hope it helps!
<h3>Learn more</h3>
- Learn more about sodium ion brainly.com/question/6839866
- Learn more about sulfate ion brainly.com/question/2763823
- Learn more about ions brainly.com/question/11852357
<h3>Answer details</h3>
Grade: 9
Subject: Chemistry
Chapter: Introduction to Mastering Chemistry
Keywords: sodium ion, sulfate ion, ions, Chemistry, symbol
a.
Acids react with bases and give salt and water and the products.
Hence, HCl reacts with NaOH and gives NaCl salt and H₂O as the products. The reaction is,
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
To balance the reaction equation, both sides hould have same number of elements.
Left hand side, Right hand side,
H atoms = 2 H atoms = 2
Cl atoms = 1 Cl atoms = 1
Na atoms = 1 Na atoms = 1
O atoms = 1 O atoms = 1
Hence, the reaction equation is already balanced.
b.
Molarity (M)= moles of solute (mol) / Volume of the solution (L)
HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
Molarity of NaOH = <span>0.13 M
</span>Volume of NaOH added = <span>43.7 mL
Hence, moles of NaOH added = 0.13 M x 43.7 x 10</span>⁻³ L
= 5.681 x 10⁻³ mol
Stoichiometric ratio between NaOH and HCl is 1 : 1
Hence, moles of HCl = moles of NaOH
= 5.681 x 10⁻³ mol
5.681 x 10⁻³ mol of HCl was in <span>26.9 mL.
Hence, molarity of HCl = </span>5.681 x 10⁻³ mol / 26.9 x 10⁻³ L
= 0.21 M
