Lets do process of elimination!
A. Breaking glass - That is a psychical change because if you break it, it is still glass. It didn't change to another substance.
B. Melting ice on a windshield - During the melting process, there is no chemical change, and therefore, no new substance is created.
C. Burning gasoline - When gas burns it usually combines with oxygen to give carbon dioxide, water etc. It is a chemical change.
D. Denting a bumper - The bumper is still a bumper, only thing is it has a dent in it. The properties did not change, meaning no chemical change.
Answer:
Weather forecasting is important to the people since it helps determine future climate expectations .
Answer:
Option B
Explanation:
The rate law is represented as
Rate of the reaction =
Here K is the rate constant
A is the concentration of substance A
B is the concentration of substance B
Hence, If reactant A is in the rate law equation, then if its concentration varies then it will impact the rate of the reaction
Hence, option B is correct
We find out the molar mass of NH₃.
atomic mass (N)=14 u
atomic mass (H)=1 u
atomic weight (NH₃)=14 u + 3(1u)=17 u
Therefore the molar mass of NH₃ will be: 17 g/mol
Then:
1 mol of water=18 g
2) We know that:
1 mol of any substance=6.022 * 10²³ particles.
3)We calculate the mass of 8.00 *10²² molecules
18 g of water----------------------------6.022*10²³ molecules
x---------------------------------------------8.00*10²² molecules
x=(18 g of water * 8.00*10²² molecules) / 6.022 * 10²³ molecules=2.39 g
Answer: the mass of 8.00 *10²² molecules of NH₃ would be 2.39 g.
Explanation:
When an atom gains or lose electrons then the atom tends to attain a negative or positive charge. Thus, the ions become charged.
Whereas when an atom is neutral then the number of electrons equals the number of protons. But when an atom becomes charged then the ions have unequal number of protons and electrons.
For example, atomic number of sodium is 11 and when it loses one electron then it attains a positive charge. The equation is as follows.
Thus, we can conclude that ions must always have an unequal number of protons and electrons.