Answer:
when the velocity of an object changes,it is acted upon by an external force
The balanced equation for the reaction between Ba(OH)₂ and HCl is ;
Ba(OH)₂ + 2HCl ----> BaCl₂ + 2H₂O
When equal volumes of both acid and base are added, the pH is 7 which means its neutral.
This means that the H⁺ ions and OH⁻ are equal and they have neutralised each other. All the ions have reacted to form water molecules.
Dissociation of base and acid are as follows;
Ba(OH)₂ ---> Ba²⁺ + 2OH⁻
1 mol of Ba(OH)₂ dissociates to 2 mol H⁺
HCl ---> H⁺ + Cl⁻
n moles of HCl give out n mol of H⁺ ions
H⁺ = OH⁻ which is why solution is neutral
then OH⁻ moles present are n mol
then Ba(OH)₂ moles present should be n/2 mol
molarity of HCl = 0.5 mol/L
since volumes are equal number of moles are directly proportional to molarity
molarity of Ba(OH)₂ = 0.5/2 = 0.25 M
Answer:
in days
Explanation:
A short term environmental change refers to changes in the environment that happens within a short period of time, for example, flooding, drought, volcanic eruptions etc. In contrast to short term environmental change, long term environmental change takes place over a long period of time hence species have a longer time to adapt to it. Short term environmental changes may or may not be caused by humans. An example of a short term environmental change caused by humans is oil spillage. Short term environmental changes may lead to the the migration of species from the ecosystem.
Short term environmental changes usually occur within a very short time. The greatest time frame in which a short term environmental change can occur is in a matter of days. Only longterm environmental changes span hundreds and thousands of years.
Answer:
The mass of one mole of water molecule = 18 ×N
A amu
Explanation: The mass of one mole of water molecule = Mass of one molecule ×N A Also mass of one mole of water is its molar mass in grams. So the mass of one mole of water is 18 g
Answer:
450.0 L.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If n and T are constant, and have different values of P and V:
<em>(P₁V₁) = (P₂V₂).</em>
<em></em>
V₁ = 760.0 L, P₁ = 450.0 mm Hg,
V₂ = ??? L, P₂ = 760.0 mm Hg (standard pressure = 1.0 atm = 760 mm Hg).
∴ V₂ = (P₁V₁)/(P₂) = (760.0 L)(450.0 mm Hg)/(760.0 mm Hg) = 450.0 L.
