Answer:
The unknown NaOH base has a concentration of 0.636M
Explanation:
<u>Step 1:</u> the balanced equation
NaOH + HCl → NaCl + H2O
This means for 1 mole of NaOH consumed there is 1 mole of HCl needed to produce 1 mole of NaCl and 1 mole of H2O
<u>Step 2</u>: Calculate moles of HCl used
Number of moles = Concentration * volume = 0.5M * 25*10^-3 L =0.0125 moles
<u>Step 3</u>: Calculate moles of NaOH
Since the mole ratio for HCl and NaOH is 1:1 this means we have 0.0125 moles of NaOH for 0.0125 moles of HCl
<u>Step 4:</u> Calculate Concentration of the unknown NaOH base
Concentration = Number of moles / Volume
Volume of NaOH = 24.64-5 =19.64 mL = 0.01964 L
Concentration = 0.0125/0.01964 = 0.636 M
The unknown NaOH base has a concentration of 0.636M
O1Fl2
1. Assume an 100g sample, so the percentage will stay the same
2. Covert each element into their molar mass
29.6/16.00=1.8 mols of O
70.4/19.00=3.7 mols of Fl
3. Divide both by the smallest value of mol
1.8/1.8=1 O
3.7/1.8=2 Fl
4. Write the empirical formula:
O1Fl2
Na2C2O4(aq) + CaCl2(aq) -----> 2NaCl(aq) + CaC2O4(s)
Here, CaC2O4(s) is a precipitate in the reaction as a result of precipitation reaction or double displacement reaction.
As we know that double displacement reaction two metal ions displaces each other from their salt solutions.
As we know that precipitation reaction is a reaction in which precipitate is formed.
It's usually water and a type of salt take the reaction between hydrochloric acid and sodium hydroxide HCl(aq)+NaOH(aq) yeilds NaCl(aq) and H2O(l)
The element that will have the lowest electronegativity is an element with a small number of valence electrons and a large atomic radius.
Electronegativity of an element is the ability or power of that element in a molecule to attract electrons to its Valence electrons. The following are the properties of electronegativity:
- It increases across a period from left to right of the periodic table,
- It decreases down the periodic table groups
- Group 1 elements are the least (lowest) electronegative elements. These elements have the lowest valence electrons with a large atomic radius.
- Group 7 elements are the most electronegative elements.
Atomic radius of elements increase down a group because of a progressive increase in the number of shells occupied by electrons which increases the size. But it decreases across a period because electrons are accommodated within the same shell leading to greater attraction by the protons in the nucleus.
Learn more about electronegativity of elements here:
brainly.com/question/20348681
