Answer:
Both oil and gasoline molecules are nonpolar, while water is polar. Nonpolar solvents have a tendency to dissolve other nonpolar molecules.
Explanation:
Molecules may be categorized as "polar" or "nonpolar" according to <em>difference in the atom's electronegativity.</em>
<u>Water is polar</u> because it consists of two types of atoms that<em> do not cancel out each other.</em> It is made of two atoms of Hydrogen and only one atom of Oxygen. This makes the Oxygen<u> partially negative</u> and the Hydrogen <u>partially positive.</u> This allows them to readily bond with other polar molecules like sugar. However, it cannot mix freely with oil and gasoline because<em> both of these are nonpolar. </em>Nonpolar molecules do not have much difference when it comes to their atoms' electronegativity. <em>Therefore, they have the tendency to dissolve molecules which are nonpolar as well. </em>This explains why oil molecules can mix freely with gasoline.
The elements in each group have the same number of electrons in the outer orbital<span>. Those </span>outer<span> electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements. Every element in the first column (group one) has one electron in its </span>outer<span> shell.</span>
Answer: The correct option is D.
Explanation: Nonmetallic minerals are the chemical elements from which no new product can be formed when they are melted. For Example: Sand, marble etc..
For the given options:
Option A: Wood is a type of cellulose and is not considered as a nonmetallic mineral resource.
Option B: Iron is an element because it is the smallest substance which cannot be broken down. It is not considered as a nonmetallic mineral resource.
Option C: Coal is a mixture of carbon compounds. This is very close to mineral but is an organic mineral because it contains carbon atom. Hence, it is not considered as a nonmetallic mineral resource.
Option D: Aggregate is formed by the collection of particles forming a whole mass. This is a non-metallic resource as it cannot form any new product.
Hence, the correct option is D.
Half life is the time taken by a radioactive isotope to decay by half its original mass.
The original mass is 200 g
Time taken is 60 hours
Final mass is 25 g
Therefore;
Final mass = Original mass × (1/2)^n; where n is the number of half lives.
25 = 200 (1/2)^n
1/8 = (1/2)^n
n = 3
Three half lives = 60 hours
1 half lives = 20 hours
Therefore; the half life of the radioactive nucleus is 20 hours
ok im not full sure man but i would say multiple voltaic cells that have spontaneous half reactions
im sorry hope it helps
