Answer:
B. 0.92 M
Explanation:
Molarity of a solution = number of moles (n) ÷ volume (V)
According to the information provided in this question;
mass of NaCl = 42g
Volume of water = 780mL
Using mole = mass/molar mass
Molar mass of NaCl = 23 + 35.5 = 58.5g/mol
mole = 42/58.5
mole (n) = 0.72mol
Volume (V) = 780 mL = 780/1000 = 0.780 L
Hence, molarity = n/V
Molarity = 0.72/0.780
Molarity = 0.923 M
The given condition is STP, under this condition, gas has a rule of 22.4 L per mole. And the given equation is already balanced. The ratio of mole number is the same as the ratio of the volume and is also the same as the ratio of coefficients. So the answer is 4.0 liters.
The complete balanced chemical
equation is:
4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 6 H2O (g)
In statement form: 4mol NH3 reacts with 5 mol O2 to produce 6
mol H2O
First let us find for the limiting reactant:
>molar mass NH3 = 17 g/mol
moles NH3 = 54/17 = 3.18 mol NH3
This will react with 3.18*5/4 = 3.97 mol O2
>molar mass O2 = 32g/mol
moles O2 = 54/32 = 1.69 mol O2
We have insufficient O2 therefore this is the limiting
reactant
From the balanced equation:
For every 5.0 mol O2, we get 6.0 mol H2O, therefore
moles H2O formed = 1.69
mol O2 * 6/5 = 2.025 mol
Molar mass H2O = 18g/mol
<span>mass H2O formed = 2.025*18 = 36.45 grams H2O produced</span>
Answer:
The possible valances can be determined by electron configuration and electron negativity
Good Luck even though this was asked 2 weeks ago
Explanation:
All atoms strive for stability. The optima electron configuration is the electron configuration of the VIII A family or inert gases.
Look at the electron configuration of the nonmetal and how many more electrons the nonmetal needs to achieve the stable electron configuration of the inert gases. Non metals tend to be negative in nature and gain electrons. ( They are oxidizing agents)
For example Florine atomic number 9 needs one more electron to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Flowrine has a valance of -1
Oxygen atomic number 8 needs two more electrons to reach a valance number of 8 electrons to equal Neon atomic number 10. Hence Oxygen has a valance charge of -2.
Non metals with a low electron negativity will lose electrons when reacting with another non metal that has a higher electron negativity. When the non metal forms an ion it is necessary to look at the electron structure to determine how many electrons the element can lose to gain stability.
For example Chlorine which is normally -1 like Florine when it combines with oxygen can be +1, +3, + 5 or +7. It can lose its one unpaired electron, or combinations of the unpaired electron and sets of the three pairs of electrons.
