Option D.
A voltaic cell need tha anode, the cathode and the electrolyt to work.
Volitmeter is just an equipment to measure the functioning of the voltaic cell.
Answer : The correct option is A.
Explanation :
Law of conservation of mass : In the chemical reaction, the mass of reactant must be equal to the mass of product.
A. 
The mass of reactant side = ![2C_4H_{10}+2Cl_2+12O_2=[8(12)+20(1)]+4(35.5)+24(16)=642g](https://tex.z-dn.net/?f=2C_4H_%7B10%7D%2B2Cl_2%2B12O_2%3D%5B8%2812%29%2B20%281%29%5D%2B4%2835.5%29%2B24%2816%29%3D642g)
The mass of product side = 
This means, the mass of product is equal to the mass of reactant. The mass remains conserved and obeys the law of conservation of mass.
The reaction B, C, D, E does not obey the law of conservation of mass.
Therefore, Only reaction A obey the law of conservation of mass.
Answer:
Avogrado's number
Explanation:
It's unniversal measure of moles
Answer:
41.54 grams of oxygen are required to burn 13.5 g of acetylene
Explanation:
The balanced reaction is:
2 C₂H₂ + 5 O₂ → 4 CO₂ + 2 H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- C₂H₂: 2 moles
- O₂: 5 moles
- CO₂: 4 moles
- H₂O: 2 moles
Being the molar mass of the compounds:
- C₂H₂: 26 g/mole
- O₂: 32 g/mole
- CO₂: 44 g/mole
- H₂O: 18 g/mole
By reaction stoichiometry, the following mass quantities of each compound participate in the reaction:
- C₂H₂: 2 moles* 26 g/mole= 52 grams
- O₂: 5 moles* 32 g/mole= 160 grams
- CO₂: 4 moles* 44 g/mole= 176 grams
- H₂O: 2 moles* 18 g/mole= 36 grams
You can apply the following rule of three: if by stoichiometry 52 grams of acetylene react with 160 grams of oxygen, 13.5 grams of acetylene react with how much mass of oxygen?

mass of oxygen= 41.54 grams
<u><em>41.54 grams of oxygen are required to burn 13.5 g of acetylene</em></u>
<u><em></em></u>
Answer:
Explanation:
The values are given in scientific notation.
Scientific notation:
Scientific notation is the way to express the large value in short form.
The number in scientific notation have two parts.
. The digits (decimal point will place after first digit)
× 10 ( the power which put the decimal point where it should be)
for example the number 6324.4 in scientific notation will be written as = 6.3244 × 10³
Ordinary notation:
The ordinary notation is expended notation of writing the numerical values which is normal way. The numbers are written as they are, without the power of 10.
a) 7.356 ×10⁻⁶ km
0.000007356 km
b) 3.02 ×10⁻⁵ g
0.0000302 g
c) 8.348 ×10⁶ Kg
8,348,000 kg
d) 7.6352 ×10⁻³ s
0.0076352 s