Magnesium and I think its MG12 for the other part
Answer:
- <em>He realized that some elements had not been discovered.</em>
Explanation:
Some scientists that tried to arrange the list of elements known before Mendeleev include Antoine Lavoisier, Johann Döbereiner, Alexandre Béguyer de Chancourtois, John Newlands, and Julius Lothar Meyer.
<em>Dimitri Mendeleev</em> was so succesful that he is recognized as the most important in such work.
Mendeleev by writing the properties of the elements on cards elaborated by him, and "playing" trying to order them, realized that, some properties regularly (periodically) repeated.
The elements were sorted in increasing atomic weight (which is not the actual order in the periodic table), but when an element did not meet the pattern discovered, he moved it to a position were its properties fitted.
The amazing creativity of Mendeleev led him to leave blanks for what he thought were places that should be occupied by elements yet undiscovered. More amazing is that he was able to predict the properties of some of those elements.
When years after some of the elements were discovered, the genius of Mendeleev was proven because the "new" elements had the properties predicted by him.
Answer:
carbon dioxide
Explanation:
Carbon burns in oxygen to form carbon dioxide. Since hydrocarbon fuels only contain two elements, we always obtain the same two products when they burn. In the equation below methane (CH 4) is being burned. The oxygen will combine with the carbon and the hydrogen in the methane molecule to produce carbon dioxide (CO 2) and water (H 2O).
Carbon, as graphite, burns to form gaseous carbon (IV) oxide (carbon dioxide), CO2. ... When the air or oxygen supply is restricted, incomplete combustion to carbon monoxide, CO, occurs. 2C(s) + O2(g) → 2CO(g) This reaction is important. When one mole of carbon is exposed to some energy in the presence of one mole of oxygen gas, one mole of carbon dioxide gas is produced. This reaction is a combustion reaction.
Answer:
Explanation:
The word computer dates to the 1600s, so if you want to know the trems etymology, you will have to start your research in the time period.
Answer:
V = 552 mL or 0.552 L
Explanation:
First, we need to calculate the number of moles of H2 using the ideal gas equation which is:
PV = nRT
Solving for n:
n = PV / RT
Where:
P = Pressure
V = Volume
R = Gas constant (0.082 L atm / K mol)
T = Temperature in K
Let's convert first both pressure in atm, remember that 1 atm = 760 mmHg
P = 735 / 760 = 0.967 atm
Pwater = 21 / 760 = 0.028 atm
Finally temperature to Kelvin:
T = 23 + 273.15 = 296.15 K
Now, at first the hydrogen was collected by water displacement so pressure is:
P = 0.967 - 0.028 = 0.939 atm
Now the moles of hydrogen:
n = 0.939 * 0.568 / 0.082 * 296.15
n = 0.022 moles
Now that we have the moles, let's calculate the volume when the pressure is 735 mmHg
V = nRT/P
V = 0.022 * 0.082 * 296.15 / 0.967
V = 0.552 L or 552 mL
This is the volume that hydrogen occupies.
