Answer:
Density, melting point. and magnetic properties
Explanation:
I can think of three ways.
1. Density
The density of Cu₂S is 5.6 g/cm³; that of CuS is 4.76 g/cm³.
It should be possible to distinguish these even with high school equipment.
2. Melting point
Cu₂S melts at 1130 °C (yellowish-red); CuS decomposes at 500 °C (faint red).
A Bunsen burner can easily reach these temperatures.
3. Magnetic properties
You can use a Gouy balance to measure the magnetic susceptibilities.
In Cu₂S the Cu⁺ ion has a d¹⁰ electron configuration, so all the electrons are paired and the solid is diamagnetic.
In CuS the Cu²⁺ ion has a d⁹ electron configuration, so all there is an unpaired electron and the solid is paramagnetic.
A sample of Cu₂S will be repelled by the magnetic field and show a decrease in weight.
A sample of CuS will be attracted by the magnetic field and show an increase in weight.
In the picture below, you can see the sample partially suspended between the poles of an electromagnet.
Answer:
F, F⁻¹, Br, Br⁻¹
Explanation:
Atomic radii:
It is the inter nuclear distance between bonded atom.
Trend along group:
When we move from top to bottom in a group atomic size increases with increase of atomic number because of addition of electron in next energy level. Thus nuclear attraction becomes weaker on valence electrons and size gets increased. Moreover shielding effect also protect the valance electrons from nuclear attraction.
when we move from bottom to top the atomic size decreases because of decrease in atomic number and energy level.
For example
In halogens the fluorine has smaller size than rest of halogens elements because it is present in top of this column. while bromine is present third to the fluorine that's why its atomic size is larger than fluorine. When an extra electron is added the atomic size becomes greater than neutral atom because of addition of electron to the next energy level. That's why anionic size is greater than neutral atom.
The given particles thus arranged in smallest to largest size in following order.
F, F⁻¹, Br, Br⁻¹
Answer:
11.9 g S
General Formulas and Concepts:
<u>Chem</u>
- Reading a Periodic Table
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
- Dimensional Analysis
Explanation:
<u>Step 1: Define</u>
2.23 × 10²³ atoms S
<u>Step 2: Define conversions</u>
Avogadro's Number
Molar Mass of S - 32.07 g/mol
<u>Step 3: Dimensional Analysis</u>
<u /> = 11.8758 g S
<u>Step 4: Check</u>
<em>We are given 3 sig figs. Follow sig fig rules.</em>
11.8758 g S ≈ 11.9 g S
<span>The answer is an equation. The equation should be balanced meaning mass on both sides of the equation, that is, products and reactants should have the same mass. This is a requirement due to the law of conservation of mass.The reactants and products are symbolized using <span>formulas.</span></span>
Answer:
KBr is dissolved in water.
Explanation:
KBr(aq)
aq means aqueous solution
That means that KBr is dissolved in water.