Hi!
When titrating Calcium and Water solution, if there is some CaCO3 in the solution, the following reactions may occur in acid solution:
CaCO₃ + H⁺ → Ca⁺² + HCO₃⁻
HCO₃⁻ + H⁺ ↔ H₂CO₃ → CO₂ (g) + H₂O
The bubbles are from CO₂ that is being developed from an acidic solution of CaCO₃
Let us assume that the ring is a size 7 ring, which has a circumference of 54.3 millimeters. Converting this to centimeters, the circumference of the ring is:
54.3 mm = 5.43 cm
Now, we determine the number of gold atoms that will be present in this:
5.43 / 1 x 10⁻⁹
There will be 5.43 x 10⁹ atoms
We now determine the number of moles this is by:
one mole = 6.02 x 10²³ atoms
Moles = 5.43 x 10⁹ / 6.02 x 10²³
Moles = 9.01 x 10⁻¹⁵ moles
The molar mass of gold is 197 g/mol
The mass is 9.01 x 10⁻¹⁵ * 197
The mass of the strand is 1.76 x 10⁻¹² grams
Answer:

Explanation:
From the question we are told that:
Chemical Reactions:
X=A⇌B,ΔG= 14.8 kJ/mol
Y=B⇌C,ΔG= -29.7 kJ/mol
Z=C⇌D,ΔG= 8.10 kJ/mol
Since
Hess Law
The law states that the total enthalpy change during the complete course of a chemical reaction is independent of the number of steps taken.
Therefore
Generally the equation for the Reaction is mathematically given by

Therefore the free energy, ΔG is



Answer:
She should suspect a Tornado.
Explanation:
Tornadoes form when warm humid air collides with cold dry air. The denser the cold air is pushed over warm air, causing an updraft. As soon as it reaches the ground a tornado is formed.
The correct answer is the second option. During fusion, uranium atoms are fused together. Fusion reaction happens when two or more nuclei combine or collide to form an element with a higher atomic number. In this process, some of the matter of the fusing nuclei is converted to energy.