Answer:
The conversion of liquid water into gaseous water is a chemical change
Explanation:
A chemical change occurs when there is a chemical reaction, so there'll be changed in the compounds, such as forming new ones, forming its elements, or elements forming compounds.
A physical change occurs when there is a change in the state of aggregation of the compound, it means that it changes its physical state. Solid for liquid, liquid for solid, liquid for gas, gas for liquid, solid for gas, and gas for solid are the physical changes.
So the evaporation of water, or its conversion in gaseous water, is a physical change, not a chemical change.
Answer:
B.) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom loses the electron.
Explanation:
Silicon is located in the 3rd row and 14th column in the periodic table. Arsenic is located in the 4th row and 15th column in the periodic table. This means that arsenic has one more valence electron than silicon. Since arsenic is located one row down from silicon, its valence electrons occupy higher energy orbitals.
Silicon maintains a crystal-like lattice structure. Each silicon atom is covalently connected to assume this shape. When silicon gains one extra electron from arsenic, it experiences n-type doping. This new electron is not tightly bound in the lattice structure. This allows it to move more freely and conduct more electricity. This can also be explained using band gaps. Silicon, which previously had an empty conduction band, now has one electron in this band. This lowers the band gap between the conduction and valence bands and increases conductivity.
Answer:
Buffer 1.
Explanation:
Ammonia is a weak base. It acts like a Bronsted-Lowry Base when it reacts with hydrogen ions.
.
gains one hydrogen ion to produce the ammonium ion 
. In other words, is the conjugate acid of the weak base .
Both buffer 1 and 2 include
- the weak base ammonia , and
- the conjugate acid of the weak base .
The ammonia in the solution will react with hydrogen ions as they are added to the solution:
.
There are more in the buffer 1 than in buffer 2. It will take more strong acid to react with the majority of in the solution. Conversely, the pH of buffer 1 will be more steady than that in buffer 2 when the same amount of acid has been added.
Hi,
Two sodium atoms are needed to create an ionic bond with sulfur.
