Answer:
Humans started to use pesticides dating back to before 2000 BC.
Hope this helps ^-^
Explanation:
45 cm^3 i think? not sure tbh sorry
Answer:
pH = 3.02
Explanation:
Acetic Acid is a weak acid (HOAc) that ionizes only ~1.5% as follows:
HOAc ⇄ H⁺ + OAc⁻.
In pure water the hydronium ion concentration [H⁺] equals the acetate ion concentration [OAc⁻] and can be determined* using the formula [H⁺] = [OAc⁻] = SqrRt(Ka·[acid]) = SqrRt(1.8x10⁻⁵ x 0.0500)M = 9.5x10⁻⁴M.
By definition, pH = -log[H⁺] = -log(9.5x10⁻⁴) = 3.02
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*This formula can be used to determine the [H⁺] & [Anion⁻] concentrations for any weak acid in pure water given its Ka-value and the molar concentration of acid in solution.
Answer:
Explanation:
We are given the mass, specific heat, and temperature, so we must use this formula for heat energy.
The mass is 5 grams, the specific heat capacity is 0.14 Joules per gram degree Celsius. Let's find the change in temperature.
- ΔT= final temperature - initial temperature
- ΔT= 95°C - 15°C = 80°C
We know the variables and can substitute them into the formula.
Multiply the first numbers. The grams will cancel.
Multiply again. This time the degrees Celsius cancel.
56 Joules of heat are needed.
The correct answer is option c, that is, nucleus.
A usual atom comprises three subatomic particles, that is, the neutrons, protons, and electrons. According to Bohr's model, the majority of the mass of an atom is in the nucleus, that is, a small, dense region at the center of each atom, comprising nucleons.
The nucleons incorporate neutrons and protons. All the positive charge of an atom is found in the nucleus and arises from the protons, the neutrons are neutrally-charged, and the electrons are the negatively charged particles found outside of the nucleus.
