Answer:
Ppm <u>means the concentration of vapors or gases</u> expressed in parts per million of polluted air.
Explanation:
In Chemistry and Physics, part per million or PPM is a measure that expresses the number of units of a certain existing substance for every million units of the mixture. (Concentration)
In climate the equation is used so:
- ppm = parts of polluted air / million parts of air
.
- ppm = Liters of polluted air / 10∧6 Liters of air.
This is used to find the concentration of gases expressed as parts of gas per million parts of the
polluted air.
In this case, it would be<u> 407.4L of CO2 per 10∧6L of air.</u>
Balanced chemical equation:
2 H2 + 1 O2 = 2 H2O
4 g H2 -------> 32 g O2 -----------> 36 g H2O
↓ ↓ ↓
14.0 g ---------> 2.0 g O2 ----------> mass H2O ?
32 * mass H2O = 2.0 * 36
32 * mass H2O = 72
mass of H2O = 72 / 32
mass of H2O = 2.25 g
hope this helps!.
Answer:
The group number in the periodic table represents number of valence electrons of the elements in a certain group.
Explanation:
There are s, p, d, and f blocks, which you can see in periodic table
The s-block and p-block together are usually considered main-group elements, the d-block corresponds to the transition metals, and the f-block encompasses nearly all of the lanthanides (like lanthanum) and the actinides (like actinium)
There are three main principles, which may useful for you:
- The Pauli exclusion rule basically says that at most, 2 electrons are allowed to be in the same orbital.
- Hund’s rule explains that each orbital in the subshell must be occupied with one single electron first before two electrons can be in the same orbital.
- The Aufbau process describes the process of adding electron configuration to each individualized element in the periodic table.
Hope this helps!
Positively charged and the sodium ion would be a cation
First choice: PhH4 has a lower boiling point
Second: SiF4 higher
Third: CBr4 higher