Answer:
The correct answer is because they have same number of protons but different number of neutrons.
Explanation:
Isotopes are atoms of the same element but differ only in the number of neutrons in the nucleus, i.e. they have same atomic number but different mass number.
Mass number is affected as they have different number of neutrons, thus effecting their physical properties.
The number of electrons and protons are same, i.e. their atomic number is same and thus their chemical properties are same as chemical properties are determined by the atom’s electronic configuration and that relates to number of protons.
Answer:
Never pour water into acid but acid into water
Explanation:
If water is poured into extremely concentrated acid/bases, the rate of volatility and exothermic reaction is too rapid and might cause a chemical eruption, leading to acid burns.
Safety precautions hence dictate the reverse is practiced.
I believe this is a clear answer.
Magnet to remove the iron, filter paper (or some filter that could trap sand) to remove the sand, and heat up the salt and water, causing the water to evaporate to separate them.
Molality can be expressed by moles of solute over
kilograms of solvent. The question asks the molality of 0.25m NaCl. 0.25m NaCl
is equal to 0.25 moles of NaCl over 1 kg of water.
Answer:
If the volume of the container is decreased by a factor of 2 the pressure is is increased by the same factor to 1664 torr.
Explanation:
Here we have Boyle's law which states that, at constant temperature, the volume of a given mass of gas is inversely proportional to its pressure
V ∝ 1/P or V₁·P₁ = V₂·P₂
Where:
V₁ = Initial volume
V₂ = Final volume = V₁/2
P₁ = Initial pressure = 832 torr
P₂ = Final pressure = Required
From V₁·P₁ = V₂·P₂ we have,
P₂ = V₁·P₁/V₂ = V₁·P₁/(V₁/2)
P₂ = 2·V₁·P₁/V₁ = 2·P₁ = 2× 832 torr = 1664 torr
