Molarity = (Mass/ molar mass) x (1/ volume of solution in Litres)
Mass = Molarity x molar mass x volume of solution in Litres
Molarity of Tris = 100 mM = 0.1 M
volume of Tris sol. = 100 mL = 0.1 L
molar mass of Tris = 121.1 g/mol
Hence,
mass of Tris = Molarity of Tris x molar mass ofTris x volume of Tris solution
= 0.1 M x 121.1 g/mol x 0.1 L
= 1.211 g
mass of Tris = 1.211 g
Since the beaker was heated we can asume that only magnesium cloride is left in the beaker, therfore the difference between the beaker with magnesium chloride and the empty beaker give the mass of magnisium chloride:
Yes, it is a special case of enthalpy of neutralization.
The enthalpy of neutralization (ΔHn) is the change in enthalpy that occurs when one equivalent of an acid and one equivalent of a base undergo a neutralization reaction to form water and a salt.
The standard enthalpy change of neutralization is the enthalpy change when solutions of an acid and an alkali react together under standard conditions to produce 1 mole of water.
Answer:
<em>The correct option is A) The atom has changed over the years.</em>
Explanation:
Option A is not correct because an atom does not change. It remains the same always. The structure of an atom will always contain neutrons, protons and electrons.
Scientific theories tend to change over time as new information is brought up. Novel techniques lead to more advanced experiments and results. As a result, a scientific theory is subjected to change whenever evidence is found for a new theory which challenges the older one.
The atomic theory has changed many times due to novel scientific techniques and experiments.
