Answer:
Explanation:
The law of conservation of mass states that mass is neither created nor destroyed during a chemical reaction. This can be gleaned from the third postulate in Dalton's series. Magnesium oxide decomposes into magnesium and oxygen. If 4.03 g of magnesium oxide decomposes to form 2.43 g of magnesium, what mass of oxygen gas is also released in the reaction
The word say magnesium oxide decomposes to magnesium and oxygen
the chemical symbols say
MgO-----------> Mg + O2 (since natural oxygen is diatomic)
the balanced equation says
2MgO-------------->2Mg + O2
4.03 gm----------> 2.43 + ?0 gms
tour high school Algebra I class says
? = 4.03 -2.43 =1.60
your chemical analytcal lab says %mO in MgO = 16/40.3 = 39.7%
your calculator says
39.7/100 X 4.03 = 1.60
all of these prove the law of conservation of mass
Answer:
8.73
Explanation:
when you are adding or subtracting numbers, the sigfig (significant figure) is based on how many numbers after the decimal. with this info, we can see that 15.67 has 2 sigfigs and 6.943 has 3 sigfigs. when you subtract normally, you would get 8.727, which has 3 sigfigs, so you would round the last 7 up to get 8.73 with 2 sigfigs!
also it is to 2 sigfigs because we know that we go by the least number of sigfigs. hope this helped!
The cell notation for the voltaic cell that incorporates the redox reaction Mg(s) + Sn²⁺(aq) → Mg²⁺(aq) + Sn(s) is Mg(s)|Mg²⁺(aq)║Sn²⁺(aq)|Sn(s).
The cell notation for a voltaic cell is the following:
anode ║ cathode
The anode is where the oxidation reaction takes place and the cathode is where the reduction happens.
The given reaction is:
Mg(s) + Sn²⁺(aq) → Mg²⁺(aq) + Sn(s)
We can see that <u>magnesium </u>is <u>oxidizing</u> (it is losing electrons) and that <u>tin </u>is <u>reducing</u> (it is gaining electrons).
These two processes can be represented in the following half-reactions:
Oxidation: Mg(s) → Mg²⁺(aq)
Reduction: Sn²⁺(aq) → Sn(s)
Which in <u>cell notation</u> is:
Anode: Mg(s)|Mg²⁺(aq)
Cathode: Sn²⁺(aq)|Sn(s)
Hence, the <u>notation</u> for the <u>voltaic cell</u> is:
Mg(s)|Mg²⁺(aq)║Sn²⁺(aq)|Sn(s)
Therefore, the cell notation for the voltaic cell with the given reaction is Mg(s)|Mg²⁺(aq)║Sn²⁺(aq)|Sn(s).
Learn more about voltaic cells here:
I hope it helps you!
Answer:
The answer is
<h2>686.01 g</h2>
Explanation:
The mass of a substance when given the density and volume can be found by using the formula
<h3>mass = Density × volume</h3>
From the question
volume of zinc = 96.08 cm³
density = 7.14 g/cm³
The mass is
mass = 96.08 × 7.14 = 686.0112
We have the final answer as
<h3>686.01 g</h3>
Hope this helps you
The Ideal Gas Law states that pressure (P) × volume (V) is equal to the # of moles (n) of the gas × a constant (R) × temperature (T), such that the equation is:
PV = nRT
At standard temp and pressure (STP), the T is 0°C or 273.15K, the P is 1 atm or 760 torr, and the R constant is 0.0821. Therefore the equation, solved for V becomes: V = nRT/P, or V = n(0.0821)(273)/1, so that it reduces to V = 22.4 Liters, when n = 1 mole.
So the V of any gas at STP is 22.4 L / mole