Answer:
The molarity of HCl is 0.138 M
Explanation:
The titration reaction is as follows:
2HCl + Ca(OH)₂ → CaCl₂ + 2H₂O
When no more HCl is left, the small excess of Ca(OH)₂ added will cause the pH to rise and the indicator will turn. At this point, the number of moles of Ca(OH)₂ added will be the same as half the number of moles of HCl since 1 mol Ca(OH)₂ reacts with 2 moles HCl. Then:
At the endpoint:
moles Ca(OH)₂ = moles HCl / 2
Knowing the number of moles of Ca(OH)₂ added, we can calculate the number of moles of the acid:
mol Ca(OH)₂ = Volume added * concentration of Ca(OH)₂
mol Ca(OH)₂ = 0.0265 l * 0.130 mol/l = 3.45 x 10⁻³ mol Ca(OH)₂
The number of moles of HCl will be:
mol HCl = 2 * 3.45 x 10⁻³ mol = 6.89 x 10⁻³ mol HCl
This number of moles was present in 50.0 ml, then, in 1000 ml:
mol of HCl in 1000 ml = 6.89 x 10⁻³ mol HCl * (1000ml / 50ml) = 0.138 mol
Then:
Molarity HCl = 0.138 M
A sample of material is found to have a mass if 33.03 grams (g), and a volume of 2.624 ml, hence the metal is Silver.
∴ Silver = 12.59 g/mL
The elements of group 11 (Cu, Ag, and Au) are called coinage metals because they are used in minting coins. These metals are malleable. They have the ability to get converted into sheets.
The coinage metal comprise, at a minimum, those metallic chemical elements which have historically been used as components in alloys used to mint coins.
The coinage metals have the highest electrical and thermal conductivities of all the metals, and they are also the most ductile and malleable.
To learn more about coinage metals here
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D.) He arranged elements by Atomic Masses
Answer:
because they react with other gases of atmosphere and pollute the environment
