Answer:
B
Explanation:
Balanced equations have the same number of elements on both sides. If the number of elements are equal to each other for every element in the equation on both sides, then the equation is balanced.
Important concept : The big number before an element or compound represents how many molecules of that compound or element there are in a reaction. To find the number of atoms of each element you multiply the coefficient by the subscript ( small number ) which represents the number of atoms of that element in each molecule. Ex. 3H2O. There is a coefficient of 3 meaning that there are 3 molecules of H2O. There is a subscript after H meaning there are 2 atoms of hydrogen in each molecule. To find the total number of atoms we multiply the subscript of hydrogen by the coefficient of the whole molecule. 3 * 2 = 6 , so there are a total of 6 atoms of hydrogen in 3H2O
A) Cu + 2AgNO3 ==> CuNO3 + 2Ag
1 Cu 1
2 Ag 2
2 N 1
3 O 3
The amount of nitrogen atoms is different on both sides of the equation therefore this is not a balanced equation
B) CCl4 + O2 ==> CO2 + 2Cl2
1 C 1
4 Cl 4
2 O 2
The number of atoms of each element is the same on both sides of the equation therefore this is the balanced equation, however lets check the other answer choices just in case.
C) 2K + H2SO4 ==> K2SO4 + 2H2
2 K 2
1 H 4
1 S 1
4 O 4
The number of Hydrogen atoms are different on each side of the equation therefore this is not a balanced equation.
D) 2Al2O3 ==> 2Al + 3O2
4 Al 2
6 O 6
There are a different amount of aluminum atoms on both sides of the equation therefore this is not a balanced equation.
Answer:
sulfur
Explanation:
In oxygen family sulfur has yellow color and also having stinky smell. Thus given statements are about sulfur.
It is present in oxygen family.
It has six valance electrons.
Its atomic number is 16.
Its atomic weight is 32 amu.
The electronic configuration of sulfur is given below,
S₁₆ = 1s² 2s² 2p⁶ 3s² 3p⁴
We can see the valance shell is third shell and it have six electrons thus sulfur have six valance electrons. (3s² 3p⁴ )
Sulfur is used in vulcanisation process.
It is used in bleach and also as a preservative for many food.
it is used to making gun powder.
Mass C₆H₈O₇ : 0.531484 g
<h3>Further explanation</h3>
Reaction
3NaHCO₃ (aq) + C₆H₈O₇ (aq) → 3 CO₂ (g) + 3 H₂O (l) + Na₃C₆H₅O₇ (aq)
MW NaHCO₃ : 84 g/mol
mass NaHCO₃ : 7.10² mg=0.7 g
mol NaHCO₃ :

mol C₆H₈O₇ :

MW C₆H₈O₇ : 192 g/mol
mass C₆H₈O₇ :

Quantitative measurements are numerical values, they involve amounts and units like measuring things. Qualitative observations appeal to the five senses, like what does the interaction look and sound like
Balanced equation : C. CH₄ + 4Cl₂⇒ CCl₄+ 4HCl
<h3>Further explanation </h3>
Equalization of chemical reactions can be done using variables. Steps in equalizing the reaction equation:
1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c, etc.
2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index (subscript) between reactant and product
3. Select the coefficient of the substance with the most complex chemical formula equal to 1
Reaction
CH₄ + Cl₂⇒ CCl₄+ HCl
aCH₄ + bCl₂⇒ CCl₄+ cHCl
C, left=a, right=1⇒a=1
H, left=4a, right=c⇒4a=c⇒4.1=c⇒c=4
Cl, left=2b, right=4+c⇒2b=4+c⇒2b=4+4⇒2b=8⇒b=4
The equation becomes :
CH₄ + 4Cl₂⇒ CCl₄+ 4HCl