Answer:
The mass is 0.855 grams (option A)
Explanation:
Step 1: Data given
aluminium sulfate = Al2(SO4)3
Numer of moles Al2(SO4)3 = 2.50 * 10^-3 moles
atomic mass Al = 26.99 g/mol
atomic mass S = 32.065 g/mol
Atomic mass O = 16 g/mol
Step 2: Calculate molar mass Al2(SO4)3
Molar mass = 2* 26.99 + 3*32.065 + 12*16
Molar mas = 342.175 g/mol
Step 3: Calculate mass Al2(SO4)3
Mass Al2(SO4)3 = moles Al2(SO4)3 * molar mass Al2(SO4)3
Mass Al2(SO4)3 = 2.5 *10^-3 moles * 342.175 g/mol
Mass Al2(SO4)3 = 0.855 grams
The mass is 0.855 grams (option A)
Answer:
c) H2O and OH−
Explanation:
Acids are the species which furnish hydrogen ions in the solution or is capable of forming bonds with electron pair species as they are electron deficient species.
When an acid donates a proton, it changes into a base which is known as its conjugate base.
Bases are the species which furnish hydroxide ions in the solution or is capable of forming bonds with electron deficient species as they are electron rich species. When a base accepts a proton, it changes into a acid which is known as its conjugate acid.
The acid and the base which is only differ by absence or presence of the proton are known as acid conjugate base pair.
Thus, for the reaction,

The base is
and the conjugate acid of the base is
.
Also, The base is
and the conjugate acid of the base is
.
<u>Correct option is :- c) H2O and OH−</u>
Answer:
the degree to which they decrease CNS activity
Explanation:
Drugs can be classified as;
✓hallucinogens, example is (LSD)
✓ stimulants, example is (cocaine)
✓opium-related painkillers example is (heroin)
✓depressants
Depressants can be regarded as medicines, that lowers neurotransmission levels, that is depressing or reducing arousal or stimulation as regards to various areas of the brain. these could be tranquilizers, as well as hypnotics and
sedatives. They are drugs used in slowing brain activity, therefore, making them useful when treating anxiety, sleep disorders, panic and acute stress reactions.
Example of Depressants are;
✓Xanax
✓Halcion
✓Klonopin
✓Librium
It should be noted that Depressants are often classified according to the degree to which they decrease central nervous system (CNS) activity.
Many transition metal ions(e.g. in soluble salt solutions) give colored hydroxide precipitates when mixed with aqueous sodium hydroxide solution. However zinc ions give a white hydroxide precipitate. These reactions can be used to help identify transition metal ions in solution.
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It should be scientific law since a hypothesis is like a prediction and a theory could be used to explain something although it might not be true. There’s many theories just to explain one thing. So it should be scientific law