Answer:
Indeed, the two samples should contain about the same number of gas particles. However, the molar mass of
is larger than that of
(by a factor of about
.) Therefore, the mass of the
sample is significantly larger than that of the
sample.
Explanation:
The
and the
sample here are under the same pressure and temperature, and have the same volume. Indeed, if both gases are ideal, then by Avogadro's Law, the two samples would contain the same number of gas particles (
and
molecules, respectively.) That is:
.
Note that the mass of a gas
is different from the number of gas particles
in it. In particular, if all particles in this gas have a molar mass of
, then:
.
In other words,
.
.
The ratio between the mass of the
and that of the
sample would be:
.
Since
by Avogadro's Law:
.
Look up relative atomic mass data on a modern periodic table:
Therefore:
.
.
Verify whether
:
- Left-hand side:
. - Right-hand side:
.
Note that the mass of the
sample comes with only two significant figures. The two sides of this equations would indeed be equal if both values are rounded to two significant figures.
Answer:
there r 118 elements in periodic table..
hope it helps.
Answer:
1. B
2. C
Explanation:
1. There are 15 electrons which means that the element is phosphorus. We know it is in the excited state because an electron from the second ring has moved to the third one, typically it would be 2 - 8 - 5.
2. An element with 3 valence electrons will be 3 spaces from the left side of the periodic table. Sodium is 1, Magnesium is 2, Aluminium is 3, and Silicon is 4. Noble gasses on the right have all 8.
Answer:
The correct option is: 4. soluble in both acidic and basic solutions
Explanation:
Oxide is a chemical compound formed by an element with oxygen. In such compounds, the oxygen is generally present in the -2 oxidation state.
Whereas, hydroxide is a chemical compound formed by an element with hydroxyl group (-OH).
<em>Oxides and hydroxides of some elements are </em><em>amphoteric</em><em> in nature.</em> <u><em>Such compounds can behave as an acid in basic medium and behave as a base in acidic medium.</em></u>
<u>Therefore, amphoteric oxides and hydroxides are soluble in both acidic and basic solutions.</u>