Answer & Explanation:
The reason why is because global fossil fuel consumption is on the rise, and new reserves are becoming harder to find. Those that are discovered are significantly smaller than the ones that have been found in the past.
Oil: Consumption (Predictions): Over 11 Billion tonnes Annually. If we carry on as we are, our known oil deposits could run out in just over 53 years.
Gas (Predictions): If we increase gas production to fill the energy gap left by oil, our known gas reserves only give us just 52 years left.
Coal: Although it’s often claimed that we have enough coal to last hundreds of years, this doesn’t take into account the need for increased production if we run out of oil and gas, our known coal deposits could be gone in 150 years.
For example, oil reserves are a good example: 16 of the 20 largest oil fields in the world have reached peak level production – they’re simply too small to keep up with global demand.
During the year of 2015, fossil fuels made up 81.5% of total U.S. energy consumption. The number is most likely increasing every year.
(fyi: the graph provided is showing future energy reserves for coal, gas and oil. approxiamately.)
Answer:
Ka = ( [H₃O⁺] . [F⁻] ) / [HF]
Explanation:
HF is a weak acid which in water, keeps this equilibrium
HF (aq) + H₂O (l) ⇄ H₃O⁺ (aq) + F⁻ (aq) Ka
2H₂O (l) ⇄ H₃O⁺ (l) + OH⁻ (aq) Kw
HF is the weak acid
F⁻ is the conjugate stron base
Let's make the expression for K
K = ( [H₃O⁺] . [F⁻] ) / [HF] . [H₂O]
K . [H₂O] = ( [H₃O⁺] . [F⁻] ) / [HF]
K . [H₂O] = Ka
Ka, the acid dissociation constant, includes Kwater.
Answer:
loses, gains
Explanation:
In the ionic compound aluminum selenide, each atom of aluminum will lose electrons while each atom of selenium will gain the electrons.
An ionic compound is an interatomic bond formed between a metal and non-metal. The metal is less electronegative compared to the non-metal. In this case, the metal will lose electrons to become positively charged whereas the non-metal, selenium will gain the electron to become negatively charged.
The electrostatic attraction between these oppositely charged ions leads to the formation of the ionic bond.
Answer:
Atomic emission spectra are produced when excited electrons return to the ground state.
Explanation:
Learning Objective
Define the law of conservation of mass
Key Points
The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations.
According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.
The law of conservation of mass is useful for a number of calculations and can be used to solve for unknown masses, such the amount of gas consumed or produced during a reaction.
Terms
reactantAny of the participants present at the start of a chemical reaction. Also, a molecule before it undergoes a chemical change.
law of conservation of massA law that states that mass cannot be created or destroyed; it is merely rearranged.
productA chemical substance formed as a result of a chemical reaction.
History of the Law of the Conservation of Mass
The ancient Greeks first proposed the idea that the total amount of matter in the universe is constant. However, Antoine Lavoisier described the law of conservation of mass (or the principle of mass/matter conservation) as a fundamental principle of physics in 1789.
Antoine LavoisierA portrait of Antoine Lavoisier, the scientist credited with the discovery of the law of conservation of mass.
This law states that, despite chemical reactions or physical transformations, mass is conserved — that is, it cannot be created or destroyed — within an isolated system. In other words, in a chemical reaction, the mass of the products will always be equal to the mass of the reactants.
The Law of Conservation of Mass-Energy
This law was later amended by Einstein in the law of conservation of mass-energy, which describes the fact that the total mass and energy in a system remain constant. This amendment incorporates the fact that mass and energy can be converted from one to another. However, the law of conservation of mass remains a useful concept in chemistry, since the energy produced or consumed in a typical chemical reaction accounts for a minute amount of mass.
We can therefore visualize chemical reactions as the rearrangement of atoms and bonds, while the number of atoms involved in a reaction remains unchanged. This assumption allows us to represent a chemical reaction as a balanced equation, in which the number of moles of any element involved is the same on both sides of the equation. An additional useful application of this law is the determination of the masses of gaseous reactants and products. If the sums of the solid or liquid reactants and products are known, any remaining mass can be assigned to gas.
