Answer:
d. Prevents a drastic change in pH when an acid or base enters a solution.
Explanation:
The purpose of a buffer is to resist pH change and keep the solution relatively stable.
Answer:
54.1 % Ca, 43.2 % O, 2.7% H
Explanation:
Molecular formula for calcium hydroxide is Ca(OH)₂
As we don't have a mass of Ca(OH)₂ to find out the percentage composition, we consider that the question refers to 1 mol of compound.
1 mol of hydroxide weighs 74.08 g
1 mol of hydroxide has 1 mol of Ca, therefore 40.08 g are Ca
2 moles of O therefore 32g are O
2 moles of H therefore 2 g are H
Percentage composition is known as (Mass of element/Total mass) . 100
- (40.08 / 74.08) . 100 = 54.1 %
- (32 / 74.08) . 100 = 43.2 %
- (2 / 74.08) . 100 = 2.7%
The relation between vapour pressure , enthalpy of vapourisation and temperature is
ln (88/ 39) = DeltaH / 8.314 (1 / 318 - 1 / 298)
0.814 = DeltaH / 8.314 (2.11 X 10^-4 )
DeltaH = -32.07 kJ
The Element that form more compounds than all the rest is Carbon.
Elements of Carbon
<span>A molecule of the compound carbon dioxide contains one atom of the element carbon and two atoms of the element oxygen. Each oxygen atom shares a double bond with the carbon atom. Carbon is the sixth element in the periodic table and occurs in pure form as coal and diamonds.
Hopefully I helped ^.^ Mark brainly if possible~
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