Answer:
A) 4P + 5O₂ → 2P₂O₅
Explanation:
A) 4P + 5O₂ → 2P₂O₅
This equation is balanced. There are four phosphorus and ten oxygen atoms are on both side of equation.
B) 5P + 4O₂ → 2P₄O₅
This equation is not balanced. There are five phosphorus and eight oxygen atoms on left, eight phosphorus ten oxygen on right side of equation.
C) 2P + O₂ → P₂O₅
This equation is not balanced. There are two phosphorus, two oxygen atoms on left and two phosphorus five oxygen on right side of equation.
D) 4P + 2O₂ → 2P₄O₅
This equation is not balanced. There are four phosphorus, four oxygen atoms on left and eight phosphorus ten oxygen on right side of equation.
Explanation:
Earthquakes. are caused by the earth's crust, more specifically, tectonic plates that float on top of molten magma. These plates bump into each other. it's the answer Earthquakes.
Answer:
(a) 0.047 g (b) 0.0016 oz (c) 0.0001 lb
Explanation:
The given mass of the sodium in the slice = 47 mg
(a) Mass has to be calculated in grams
The conversion of mg to g is shown below as:
1 mg = 10⁻³ g
So,
<u>Mass of sodium = 47 × 10⁻³ g = 0.047 g</u>
(b) Mass has to be calculated in ounces
The conversion of ounces to g is shown below as:
453.6 g = 16 oz
Or,
1 g = 16 / 453.6 oz
So,
<u>Mass of sodium = (0.047 × 16) / 453.6 oz = 0.0016 oz</u>
(c) Mass has to be calculated in pounds
The conversion of pounds to g is shown below as:
1 lb = 453.6 g
Or,
1 g = 1/ 453.6 lb
So,
<u>Mass of sodium = (0.047 × 1) / 453.6 oz = 0.0001 lb</u>
Answer : The enthalpy of the reaction is, -2552 kJ/mole
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given enthalpy of reaction is,
The intermediate balanced chemical reactions are:
(1) 
(2) 
(3) 
(4) 
Now we have to revere the reactions 1 and multiple by 2, revere the reactions 3, 4 and multiple by 2 and multiply the reaction 2 by 2 and then adding all the equations, we get :
(when we are reversing the reaction then the sign of the enthalpy change will be change.)
The expression for enthalpy of the reaction will be,
Therefore, the enthalpy of the reaction is, -2552 kJ/mole
Buffer solution resist the change in pH upon addition of small amount of strong acid or strong base.
Buffer consists of weak acid as HF / and its conjugate base NaF
When strong acid as HCl is added to buffer, it respond with its conjugate base to convert the strong acid to weak acid like this:
HCl (S.A) + NaF → NaCl + HF (W.A)
moles of HF we already have = M * V(in liters)
= 0.0955 M * 0.033 L = 3.15 x 10⁻³ mole
moles of HCl added = 8.00 x 10⁻⁵ mole
one mole HCl reacts with 1 mole NaF to give 1 mole HF
so the amount added to HF = 8.00 x 10⁻⁵
Total moles of HF present = (3.15 x 10⁻³) + (8.00 x 10⁻⁵) = 3.23 x 10⁻³ mole
