The balanced equation for the above double displacement reaction is as follows;
2KCl + Pb(NO₃)₂ ---> PbCl₂ + 2KNO₃
Stoichiometry of KCl to PbCl₂ is 2:1
This means that 2 mol of KCl would react with every 1 mol of PbCl₂
The molarity of KCl - 0.596 M
in 1 L of KCl there are 0.596 mol
Therefore in 10.0 mL of KCl there are -
Number of KCl moles reacted - 0.00596 mol
according to stoichiometry
number of PbCl₂ moles formed - 1/2 x number of KCl moles reacted
Therefore number of PbCl₂ moles formed - 0.00596 mol/2 = 0.00298 mol
molar mass of PbCl₂ - 278 g/mol
mass of PbCl₂ formed - 278 g/mol x 0.00298 mol = 0.828 g
Answer:
4.907 × 10^-19 J
Explanation:
The energy of the lasers in a Blu-ray player can be calculated by using;
E = hf
Where;
E = Energy of laser (J)
h = Planck's constant (6.626 × 10^-34 J/s)
f = frequency (Hz)
However, the frequency must be known first in order to calculate the energy. The frequency can be calculated using the formula:
f = v/λ
Where:
λ = wavelength (4.05x10−7 m.)
v = speed of light (3 × 10^8m/s)
f = frequency (Hz)
f = 3 × 10^8 ÷ 4.05 x 10^−7
f = 0.7407 × 10^(8 + 7)
f = 0.7407 × 10^15
f = 7.407 × 10^14 Hz
Using E = hf
E = 6.626 × 10^-34 × 7.407 × 10^14
E = 49.07 × 10^(-34 + 14)
E = 49.07 × 10^-20
E = 4.907 × 10^-19 J
Answer is: MgF₂, magnesium fluoride.
Magnesium fluoride is salt, ionic compound, because magnesium is metal from 2. group of Periodic table of elements and has low ionisation energy and electronegativity, which means it easily lose valence electons, fluorine is nonmetal with greatest electronegativity, which meand it easily gain electron, so magnesium cation (Mg²⁺) and fluorine anion (F⁻) are formed.
<u>Answer:</u>
<em>B Mass </em>
<em>D Force </em>
<em>E Acceleration</em>
<u>Explanation:</u>
We know that
Force = mass × acceleration
F = m × a
The unit of force is newtons
The unit of mass is kg and
the unit of acceleration is
Force and acceleration are vector quantities and mass is a scalar quantity.
Newton's 2nd law of motion states that acceleration is directly proportional to net force and inversely proportional to mass.
he result is the equation
∑
Explanation:
It is necessary that the glassware which we use during titration needs to be clean and dry before use because otherwise the remaining reagents will get mixed up with the solutions.
As a result, this will lead to a change in analysis results.
Hence, an error will occur in the resulting values.
Also, when not cleaned properly the any other substance remaining in the glassware might react with the solution leading to a change in the solution.
In that case also, error will occur.