Answer:
0.077 M
Explanation:
Molarity is the representation of the solution.
Molarity:
It is amount of solute in moles per liter of solution and represented by M
Formula used for Molarity
M = moles of solute / Liter of solution . . . . . . . . . . (1)
Data Given :
The concentration of half normal (NaCl) saline = 0.45g / 100 g
So,
Volume of Solution = 100 g = 100 mL
Volume of Solution in L = 100 mL / 1000
Volume of Solution = 0.1 L
molar mass of NaCl = 58.44 g/mol
Now to find number of moles of Nacl
no. of moles of NaCl = mass of NaCl / molar mass
no. of moles of NaCl = 0.45g / 58.44 g/mol
no. of moles of NaCl = 0.0077 g
Put values in the eq (1)
M = moles of solute / Liter of solution . . . . . . . . . . (1)
M = 0.0077 g / 0.1 L
M = 0.077 M
So the molarity of half-normal saline solution (0.45% NaCl) = 0.077 M
<h2>
Explanation:</h2><h3 /><h3>Oxygen- gains 2 electrons to form ions</h3><h3>Fluorine- gains 1 electron to form negative ions</h3><h3>Aluminum - loses three electrons to form ions</h3><h3>Calcium- loses 2 electrons in order to form ions</h3>
<h3>*Non metals gain electrons to form ions</h3><h3>*Metals loses electrons to form ions</h3>
Answer:
106,504 g/mol
Explanation:
The two repeat units at the polymer are the acrylonitrile and the butadiene. If the fraction of repeat of butadiene is 0.27, the fraction of repeat of units of acrylonitrile must be 0.73.
The acrylonitrile repeat unit has 3 carbons atoms, 1 nitrogen atom, and 3 hydrogen atoms. So, the molecular weigth for it is:
mac = 3*mC + 1*mN + 3*mH
mC = 12 g/mol; mN = 14 g/mol; mH = 1g/mol
mac = 3*12 + 14 + 3*1 = 53 g/mol
The butadiene repeat unit has 4 carbons atoms and 6 hydrogen atoms. Thus, the molecular weight is:
mbu = 4*12 + 6*1 = 54 g/mol
The average repeat unit molecular weight is the fractions multiplied by the molecular weight of the repeat unities:
m = 0.73*53 + 0.27*54 = 53.27 g/mol
The number-average molecular weight is the average repeat unit molecular weight multiplied by the degree of polymerization:
M = 53.27*2000
M = 106,504 g/mol
Isotopes of same element has different number of neutrons with different masses and having same number of protons and electrons.
Radioactive isotopes are those isotopes which are radioactive in nature. The unstable nucleus results in the radioactivity process and this process will go on until the stable isotope (element) forms.
Thus, the nucleus of unstable isotopes of an element will decay leading to emission of radiation.
Answer:
Here's what I get
Explanation:
(i) Voltaic cell
A voltaic cell is a device that uses a chemical reaction to produce electrical energy.
(ii) Overall Cell Potential
The standard reduction potentials for the half-reactions are
<u>ℰ°/V
</u>
Cu²⁺ + 2e⁻ ⇌ Cu 0.34
Zn²⁺ + 2e⁻ ⇌ Zn -0.76
The half-reaction with the more positive potential is the reduction half-reaction. It is the reaction that occurs at the cathode.
The half-reaction with the more negative potential is the oxidation half-reaction. It is the reaction that occurs at the anode.
We reverse that half-reaction and subtract the voltages to get the cell reaction.
<u> ℰ°/V
</u>
Cathode: Cu²⁺ + 2e⁻ ⇌ Cu 0.34
<u>Anode: Zn ⇌ Zn²⁺ + 2e⁻ -0.76</u>
Cell: Zn + Cu²⁺ ⇌ Zn²⁺ + Cu 1.10
(iii) Diagram
The specific labels will depend on your textbook.
They are often as follows.
a. Electron flow
b. Voltmeter or lightbulb
c. Electron flow
d. Cathode or Cu
e. Cu²⁺(aq) and NO₃⁻(aq)
f. Salt bridge
g. Zn²⁺(aq) and NO₃⁻(aq)
h. Anode or Zn
The salt bridge enables ions to flow in the internal circuit and to maintain electrical neutrality in the two compartments.
It often consists of a saturated solution of KCl.
As Zn²⁺ ions form in the anode compartment, Cl⁻ ions move in to provide partners for them.
As Cu²⁺ ions are removed from the cathode compartment, K⁺ ions move in to replace them.
