Your answer should be c I think
Answer:
1700 kj
Explanation:
The given reaction is exothermic reaction.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Chemical equation:
2Al + Fe₂O₃ → Al₂O₃ + 2Fe + 850 Kj
when one mole of Fe₂O₃ react 850 kj energy is produced.
when 2 moles react,
2 × 850 kj = 1700 kj
Given that CaCl2 = 2.46 m
Therefore 2.46 mole of CaCl2 present in 1.00 g of solution
Mass of 2.46 mole CaCl2= number of mole * molar mass
= 2.46 mole * 110.98 g/mol
= 273.01 g
Mass of water or solvent = mass of solution – mass of solute
= 1000 g -273.01 g
= 726.99 g
Mole of water = amount in g / molar mass
= 726.99 g/18.02 g/ mole
= 40.34 moles
Mole fraction of CaCl2 = number of mole of CaCl2 / total moles
= 2.46 /2.46+40.34
= 2.46/42.8
= 0.057
Answer:
Sodium dihydrogenphosphate = NaH₂PO₄
Sodium monohydrogenphosphate = Na₂HPO₄
Explanation:
A buffer solution is a solution is a solution that resists changes to its oH when a little quantity of strong acid or strong base is added to it.
They are solutions of weak acids or weak bases and their salts known as conjugate base or conjugate acids respectively for the weak acids and weak bases.
For example, a solution of the weak acid ethanoic acid and its salt or conjugate base, sodium ethanoate serves as a buffer solution.
In biochemical experiments, where the pH of the reaction medium is kept as constant and as close as possible to that of the internal environment, buffer solutions are widely used. One of the commonly used buffers is the phosphate buffer. The phosphate buffer consists of the acid salts sodium dihydrogenphosphate and sodium monohydrogenphosphate. Sodium dihydrogenphosphate serves as the weak acid while sodium monohydrogenphosphate serves as the conjugate base.
The formulas of these two compounds are given below:
Sodium dihydrogenphosphate = NaH₂PO₄
Sodium monohydrogenphosphate = Na₂HPO₄
Answer:
D) The sun is a burning ball of gas, and the moon revolves around a planet.
Explanation:
Unlike what Jack has written in his table, the sun is comprised of 92% gas and has no definable rocky layer or even dust. The moon revolves specifically around the Earth.