Answer:
helium , krypton,xenon,radon, argon are noble gasses
one mole of P weights about 31 grams
in one mole there are 6.022*10^23 atoms
we use the rule of threes
6.022*10^23atoms......weight..........31 grams
3.45*10^23 atoms.........weight...........x grams
x=(3.45*10^23*31)/6.022*10^23
x=106.95/6.022=<u><em>17.76 grams</em></u>
Answer: Elements in Group 2
Explanation: The periodic table was arranged by Dmitri Mendeleev specifically around similarites in their chemical behaviors. He found that as atomic number increases, at some point an element starts to react in a manner similar to a previous one. When that happened, he would place the larger element under the smaller one, and eventually noticed a periodicity in the table. Elements in a column (Groups) had similiar chemical properties. We know today that these similarities are due to the electron configuration, and that these configurations repeat themselves. He left gaps in the table when he could find an existing element with properties similar to others in that group. I big leap of faith, but it worked. Elements for those missing boxes were eventually discovered.
Answer:
V2= 1.03L
Explanation:
Start off with what you are given.
V^1: 1.00L
T^1: 23°C
V^2?
T^2: 33°C
If you know your gas laws, you have to utilise a certain gas law called Charles' Law:
V^1/T^1 = V^2/T^2
Remember to convert Celsius values to Kelvin whenever you are dealing with gas problems. This can be done by adding 273 to whatever value in Celsius you have.
(23+273 = 296) (33+273 = 306)
Multiply crisscross
1.00/296= V^2/306
296V^2 = 306
Dividing both sides by 296 to isolate V2, we get
306/296 = 1.0337837837837837837837837837838
V2= 1.03L
