Answer:
have different properties from the elements they are made from
Explanation:
Compounds have different properties from the elements they are made from. Compounds are substances composed of two or more kinds of atoms/elements joined together in a definite grouping.
- The properties of a compound are distinct and different from those of the individual elements that are combined in its make-up.
- There are several millions of compounds that are known.
- These are derived from elements.
Answer:
Approximately 2000 J.
General Formulas and Concepts:
<u>Thermodynamics</u>
Specific Heat Formula: q = mcΔT
- <em>q</em> is heat (in J)
- <em>m</em> is mass (in g)
- <em>c</em> is specific heat (in J/g °C)
- ΔT is change in temperature (in °C or K)
Explanation:
<u>Step 1: Define</u>
<em>Identify variables</em>
[Given] <em>c</em> = 0.897 J/g °C
[Given] <em>m</em> = 79 g
[Given] ΔT = 28°C
[Solve] <em>q</em>
<em />
<u>Step 2: Solve for </u><em><u>q</u></em>
- Substitute in variables [Specific Heat Formula]: q = (79 g)(0.897 J/g °C)(28 °C)
- Multiply [Cancel out units]: q = (70.863 J/°C)(28 °C)
- Multiply [Cancel out units]: q = 1984.16 J
<u>Step 3: Check</u>
<em>Follow sig fig rules and round. We are given 2 sig figs as our lowest.</em>
1984.16 J ≈ 2000 J
Answer:
Explanation:
There are four quantum numbers:
Principal quantum number (n)
Azimuthal quantum number (l)
Magnetic quantum number (ml)
Spin quantum number (ms)
All these four quantum numbers gives complete information about an electron like its spin, shells, subshells and orbitals.
For example:
If l=3 than possible sets of quantum numbers are:
Azimuthal quantum number (l)
The azimuthal quantum number describe the shape of orbitals. Its value for s, p, d, f... are 0, 1, 2, 3. For l=3
(n-1)
4-1 = 3
it means principle quantum is 4 and electron is present in f subshell.
Magnetic quantum number (ml)
It describe the orientation of orbitals. Its values are -l to +l. For l=3 the ml will be -3 -2 -1 0 +1 +2 +3.
Spin quantum number (ms)
The spin quantum number tells the spin of electron either its clock wise (+1/2) or anti clock wise (-1/2).
If the electron is added in full empty orbital its spin will be +1/2 because it occupy full empty. If electron is already present and another electron is added then its spin will be -1/2.
Answer:
1.3 M.
Explanation:
- We need to calculate the mass of the solution:
mass of the solution = mass of MgCl₂ + mass of water
mass of MgCl₂ = 20.1 g.
mass of water = d.V = (157.0 mL)(1.0 g/cm³) = 157.0 g.
∴ mass of the solution = mass of MgCl₂ + mass of water = 20.1 g + 157.0 g = 177.1 g.
- Now, we can get the volume of the solution:
V of the solution = (mass of the solution)/(density of the solution) = (177.1 g)/(1.089 g/cm³) = 162.62 mL = 0.163 L.
Molarity is the no. of moles of solute dissolved in a 1.0 L of the solution.
M = (no. of moles of MgCl₂) / (Volume of the solution (L)).
<em>∴ M = (mass/molar mass)of MgCl₂ / (Volume of the solution (L)) =</em> (20.1 g/95.211 g/mol) / (0.163 L) = <em>1.29 M ≅ 1.3 M.</em>
