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:
181 picometers is the radius of a gallium atom.
Explanation:
Primitive cubic cell is an arrangement in which constituent particles are present only at the corners of the cube.Also known as simple unit cell. In this arrangement number of total particles is equal to 1.
Gallium crystallizes in a primitive cubic unit cell.
Edge length of cubic unit cell = a = 362 pm
Let the radius be gallium atom be r
Two atoms of gallium touching each other = a =2r
362 pm = 2r
r = 181 pm
181 picometers is the radius of a gallium atom.
Answer:
Coefficient of is more than 4
Explanation:
Oxidation:
- Balance charge: ......(1)
Reduction:
- Balance Cr:
- Balance O and H in acidic medium:
- Balance charge: .......(2)
gives balanced equation:
So coefficient of is more than 4
Answer:
Calcium chloride cannot melt the ice at -20°C. Cryoscopy is the method of determining a decrease in melting point due to dissolved substances.
Answer: The categories of intermolecular forces in the molecules above are dispersion forces, dipole forces, hydrogen bonding.
Explanation:
Here are the different kinds of intermolecular forces present in the above;
Ethane - C2H6 has London dispersion forces—it’s a nonpolar covalent compound— and no other intermolecular attractions.
Dimethyl ether - CH₃OCH₃ has London dispersion force, dipole-dipole attraction, and hydrogen bonding
Ethanot- C2H5OH has has London dispersion force, dipole-dipole attraction, and hydrogen bonding