Answer:
3.78x10^23 moles and 17.04 grams
Explanation:
N/A
Answer:
C2H2O4
Explanation:
To get the molecular formula, we first get the empirical formula. This can be done by dividing the percentage compositions by the atomic masses. The percentage compositions are shown as follows :
C = 26.86%
H = 2.239%
O = 100 - ( 26.86 + 2.239) = 70.901%
We then proceed to divide by their atomic masses. Atomic mass of carbon is 12 a.m.u , H = 1 a.m.u , O = 16 a.m.u
The division is as follows:
C = 26.86/12 = 2.2383
H = 2.239/1 = 2.239
O = 70.901/16 = 4.4313
We now divide each by the smallest number I.e 2.2383
C = 2.2383/2.2383 = 1
H = 2.239/2.2383 = 1
O = 4.4313/2.2383 = 1.98 = 2
Thus, the empirical formula is CHO2.
To get the molecular formula, we use the molar mass .
(CHO2)n = 90
We add the atomic masses multiplied by n.
(12 + 1 + 2(16))n = 90
45n = 90
n = 90/45 = 2.
Thus , the molecular formula is C2H2O4
Answer:
2Na + 2H2O ----> 2NaOH + H2
Explanation:
Explanation:
Before proceeding to answering the questions, let us go over some definitions.
pH scale: The pH scale measures how acidic or basic a substance is. The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic.
pH stands for Potential of Hydrogen. It refers to the hydrogen ion concentration in a solution.
The keywords being; Hydrogen Ion concentration.
A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction.
A Lewis acid is any substance that can accept a pair of nonbonding electrons. It is an electron pair acceptor.
An Arrhenius acid is a substance that dissociates in water to form hydrogen ions or protons.
Based on the definitions of given above, it is obseved that both Bronsted lowry and arrhenius acids deals with hydrogen ions. Hence both of this acids can be measured using the pH scale. The lewis acid on the other hand do not necessarily contain hydrogen ions, hence the pH scale cannot be utilized for it.
Examples includes;
Arrhenius acid; Nitric Acid – HNO3 etc
Lewis acid; boron trifluoride (BF3) and aluminum fluoride (AlF3) etc
Bronsted lowry acid; HCl etc
Answer: C) Roman numeral following the name.
Explanation: If we want to name an ionic compound like NaCl then we can easily write its name. Na is sodium and Cl is chlorine. First we write the name of the metal ion and then the name of the anion it has. Here we have mono atomic ion and for these we use the suffix -ide. So, the name will be sodium chloride.
Now, if we have something like
and we write the name as Iron chloride, then it will not be correct since Fe is a transition metal and it shows +2 and +3 oxidation states. So, to overcome this difficulty, a roman numeral is used for the oxidation state of the metal ion. The name of above compound will be Iron(III)chloride. Similarly, if we have
then its name will be written as Iron(II)chloride.
In both the above names, the roman numerals (III) and (II) are indicating numerical value of the charge of the metal ion. So, the correct choice is C) Roman numerals following the name.
when naming a transition metal ion that can have more than one common ionic charge, the numerical value of the charge can be indicated by a Roman numeral following the name.