Answer:
0.01395mol Cr2O3
Explanation:
the molar mass of Cr2O3 is 151.9904 g/mol
2.12g Cr2O3 x 1 mol/151.9904g = 0.01395mol Cr2O3
Answer:
v = 7.3 × 10⁶ m/s
Explanation:
Given data:
Velocity of electron = ?
Wavelength = 100 pm
Solution:
Formula:
λ = h/mv
λ = wavelength
h = planck's constant
m = mass
v = velocity
Now we will put the values in formula.
100 ×10⁻¹² m = 6.63 × 10⁻³⁴ j.s / 9.109 × 10⁻³¹ kg × v
v = 6.63 × 10⁻³⁴ kg.m²/s / 9.109 × 10⁻³¹ kg ×100 ×10⁻¹² m
v = 6.63 × 10⁻³⁴ m/s /910.9 × 10⁻⁴³
v = 0.0073 × 10⁹ m/s
v = 7.3 × 10⁶ m/s
No, this item is not made of pure silver because if it has been made from pure silver that it would have displaced only 1.16cm³ of water but due to the addition of some other low-density element it displaces 1.9cm³ of water.
<u>For pure silver</u>
density of pure silver is = 10.49 g/cm³
mass of silver = 12.2 gram
since, density = mass/volume
volume = mass/density
= 12.2/10.49 cm³
= 1.16 cm³
But the actual displaced water is <u>1.9cm³</u>, which means some other element of lower density has been added.
Therefore, it is clear that the given jewelry is not made of pure silver.
Learn more about silver here:-brainly.com/question/17086277
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Answer:
Fluids (air/water) either as water vapour or oxygen and carbon dioxide.
Explanation:
Heat transfer occurs through conduction, convection or radiation.
Many aties, this involves fluids whose molecules have been activated by heated by heat, moving from hotter to cooler regions, allowing for heating or cooling of the rooms.
Building materials have varying conductivity.
First let us calculate for the molar mass of ibuprofen:
Molar mass = 13 * 12 g/mol + 18 * 1 g/mol + 2 * 16 g/mol
Molar mass = 206 g/mol = 206 mg / mmol
Calculating for the number of moles:
moles = 200 mg / (206 mg / mmol)
moles = 0.971 mmol = 9.71 x 10^-4 moles
Using the Avogadros number, we calculate the number of
molecules of ibuprofen:
Molecules = 9.71 x 10^-4 moles * (6.022 x 10^23 molecules
/ moles)
<span>Molecules = 5.85 x 10^20 molecules</span>