Answer:
A) Ca(s) + C(s) + 3/2 O₂(g) → CaCO₃(s)
Explanation:
Standard enthalpy of formation of a chemical is defined as the change in enthalpy durin the formation of 1 mole of the substance from its constituent elements in their standard states.
The consituent elements of calcium carbonate, CaCO₃, in their standard states (States you will find this pure elements in nature), are:
Ca(s), C(s) and O₂(g)
That means, the equation that represents standard enthalpy of CaCO₃ is:
<h3>A) Ca(s) + C(s) + 3/2 O₂(g) → CaCO₃(s)</h3><h3 />
<em>Is the equation that has ΔH° = -1207kJ/mol</em>
Making an atom or a virus structure
Answer:
Genetic equilibrium is the state in which allele frequencies do
not change in a generation over generation.
Explanation:
Genetic equilibrium can be described as a situation which arises when a certain allele or genotype remains constant for a species generation over generations. Genetic equilibrium can be maintained if no external factors like mutations affect the population of the species. The phenomenon of natural selection and evolution need to be stopped if a genetic equilibrium is to be maintained. Hardy-Weinberg theorem is the mathematical depiction of genetic equilibrium.
The mass of nitroglycerin : 34.52 g
<h3>Further explanation</h3>
Reaction
4C₃H₅N₃O₉ ⇒ 12 CO₂ + 10H₂O + 6N₂ +O₂
Volume = 10 L
Temperature = -5°C=268 °K
Pressure = 1 atm
mol of CO₂ (ideal gas) :
mol ratio C₃H₅N₃O₉ : mol CO₂= 4 : 12, so mol C₃H₅N₃O₉ :
mass C₃H₅N₃O₉ (MW=227,0865 g/mol):
The melting point of pure lead : 327 °C
<h3>Further explanation</h3>
Given
Amount of tin and melting point of solder
Required
The melting point
Solution
The composition of solder = tin and lead
So if it is 100% tin, 0% lead or 0% tin, 100% lead
From the table it is shown that when the position is 100% tin in the solder, the melting point of the solder is 232 °C, so it shows that the melting point of pure lead is obtained when% tin in solder = 0 (100% lead in solder), so that the melting point is obtained. : 327 °C
