Answer:
expands
Explanation:
Most substances become increasingly compressed when frozen solid, but water is a famous exception.
Answer : The correct option is, 0.21 moles
Solution : Given,
Molarity of the solution = 0.85 M = 0.85 mole/L
Volume of solution = 250 ml = 0.25 L 
Molarity : It is defined as the number of moles of solute present in one liter of the solution.
Formula used :

Now put all the given values in this formula, we get the moles of solute of the solution.


Therefore, the moles of solute is, 0.21 moles
Answer:
9.430 * 10¹⁷ protons per second whill shine on the book from a 62 W bulb
Explanation:
To answer this question, first let's calculate the energy of a single photon with a wavelength (λ) of 504 nm:
E = hc/λ
Where h is Planck's constant (6.626*10⁻³⁴ J·s) and c is the speed of light (3*10⁸ m/s).
E = 6.626*10⁻³⁴ J·s * 3*10⁸ m/s ÷ (504*10⁻⁹m) = 3.944 * 10⁻¹⁹ J.
So now we can make the equivalency for this problem, that
<u>1 proton = 3.944 * 10⁻¹⁹ J</u>
Now we convert watts from J/s to proton/s:
1
= 1 W
Solving the problem, a 62 W bulb converts 5% of its output into light, so:
3.1 watts are equal to [ 2.535*10¹⁸ proton/s * 3.1 ] = 7.858 * 10¹⁸ proton/s
Of those protons per second, 12% will shine on the chemistry textbook, thus:
7.858 * 10¹⁸ proton/s * 12/100 = 9.430 * 10¹⁷ protons/s
When the salt AgI dissolves in water it dissociates as follows;
AgI ---> Ag⁺ + I⁻
molar solubility is the number of moles that are dissolved in 1 L of solution.
If molar solubility of AgI is x, then molar solubility of Ag⁺ is x and I⁻ is x.
the formula for solubility product constant - ksp of AgI is given below
ksp = [Ag⁺][I⁻]
ksp = (x)(x)
ksp = 8.51 x 10⁻¹⁷
therefore,
x² = 8.51 x 10⁻¹⁷
x = 9.22 x 10⁻⁹
since molar solubility of AgI is x, then molar solubility of AgI is 9.22 x 10⁻⁹ M
Answer:
so the correct answer would be the 3rd one.
26 proton, 32 neutrons, 26 electrons.
Explanation:
Protons and electrons are the same, which is also the same as the atomic number. in that case that would be 26.
Therefore, proton=electron =26
for neutron, you just have to subtract the mass number to the electron/proton.
n = m - e
n= 58-26
neutron =32.
Hope that helps.