Answer:
I. A polyprotic, weak acid
II. Na2HPO4
Explanation:
Buffer solutions are those that, upon the addition of an acid or base, are capable of reacting by opposing the part of the basic or acid component to keep the pH fixed.
Buffers consist of hydrolytically active salts that dissolve in water. The ions of these salts are combined with acids and alkalis. These hydrolytically active salts are the products that result from the reaction between weak acids and strong alkalis such as calcium carbonate (from carbonic acid and calcium hydroxide) or between strong acids and weak alkalis such as ammonium chloride (a from hydrochloric acid and ammonium hydroxide).
A buffer acid reacts when a weak acid or weak base is combined with its corresponding hydrolytic salt in a water solution, a buffer system called a buffer is formed. As in this case a weak polyrotic acid with Na2HPO4, which allows the solution to be maintained at a pH of 3.8 against small aggregate amounts of both acid and base, thus favoring the reaction at a pH of 3.8
A buffer system is not always appropriate, because the ions of some hydrolytic salts can, for example, damage organisms that come into contact with it.
A mineral is a naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties. ... A rock is an aggregate of one or more minerals, or a body of undifferentiated mineral matter.
The molar mass of Calcium hydroxide is 74 g/mol
To find the percent composition we have to find the number of atoms of each element in the formula .
So there’s
Calcium - 1
Oxygen - 2
Hydrogen - 2
Then have to multiply the relative atomic mass of each element by the number of atoms
Ca - 40 g/mol x 1 = 40
O - 16 g/mol x 2 = 32
H - 1 g/mol x 2 = 2
Then To find percent composition of each element we have to divide the mass of each element in the formula by the relative molecular mass of calcium hydroxide
Ca - 40 / 74 x 100 % = 54.0%
O - 32 / 74 x 100 % = 43.2 %
H - 2 / 74 x 100 % = 2.7%
From the options given correct answer is 3rd option
54.0% Ca , 43.0% O and 2.7 % H
<span>Because you've added coefficients to the molecules on the right side of the equation, the number of oxygen atoms has changed. ...Add a coefficient of 5 to the oxygen molecule on the left side of the equation. ...<span>C3H8 + 5O2 --> 4H2O + 3CO2.</span><span>The carbon, hydrogen, and oxygen atoms are balanced</span></span>
Answer:
Explanation:
(1) 1-methylbutane
(2) 1,1,3-trimethylhexane
(3) 5octyne
(4)2-ethyl-1-propanol
(5)2,2-dimethyl1-3-butanol