Answer:
Number of moles = 0.042 mol
Explanation:
Given data:
Number of moles = ?
Mass of calcium carbonate = ?
Solution:
Formula:
Number of moles = mass/ molar mass
now we will calculate the molar mass of calcium carbonate.
atomic mass of Ca = 40 amu
atomic mass of C = 12 amu
atomic mass of O = 16 amu
CaCO₃ = 40 + 12+ 3×16
CaCO₃ = 40 + 12+48
CaCO₃ = 100 g/mol
Now we will calculate the number of moles.
Number of moles = 4.15 g / 100 g/mol
Number of moles = 0.042 mol
Answer:
the lighter fresh water rises up and over the salt water
Explanation:
this is because the salt water is denser
Answer:
Choose the least electronegative atom other than H.
Explanation:
A Lewis structure consists of <em>terminal atoms</em> and one or more <em>central atoms</em>.
H can be <em>only a terminal atom</em> because it can form only one bond.
So the central atom must be either C or O.
The central atom is the less electronegative atom: C.
So, start the Lewis structure with a central C atom.
Then attach an O atom to get C-O.
Finally, attach the H atoms.
The condensed formula often gives you a clue where they go.
The formula CH₃OH implies that there are 3 H atoms on C and one on O.
The connectivity of the atoms is then as in the diagram below.
Answer:
1s2 2s2 2p6 3s2 3p4
Explanation:
For ground state atoms you need to fill the orbitals in order.
Orbital s has max 2 electrons
Orbital p has max 6 electrons
Level 1 only has s orbital
Level 2 has s and p orbitals
Level 3 has s, p and d orbitals
You fill them in order until you reach 16 electrons:
1s2 2s2 2p6 3s2 3p4
Answer:
See explanation
Explanation:
According to the Bohr model of the atom, electrons are found in energy levels. Energy is absorbed or emitted when an electron moves from one energy level to another.
During flame test, electrons absorb energy and move to higher energy levels; they quickly return to ground state and emit the energy previously absorbed as a photon of light. This is seen as the colour imparted to the flame by the metal.
The emission spectrum tells us about the range of wavelengths emitted by an atom or compound when it is excited. At an atomic level, the electrons are moved to higher energy levels and as they return to ground state, they emit the various wavelengths that comprise the emission spectrum of any particular substance.