An electron is a negatively charged subatomic particle present in the space outside the nucleus of an atom. The loss of electron from an atom results in the formation of cation whereas gaining of electron by an atom results in the formation of anion. The cation possesses positive charge due to loss of electron and anion possesses negative charge due to gain of electron.
The neutral atom has no charge on it.
For given atomic symbols:
The atomic number of hydrogen is 1 and the given symbol has no charge that means it is in its neutral state. So, the number of electrons in 
is 1.
The atomic number of helium is 2 and the given symbol has no charge that means it is in its neutral state. So, the number of electrons in 
is 2.
The atomic number of hydrogen is 1 and the given symbol has a negative charge that represents a gain of electron. So, the number of electrons in 
is 2.
The atomic number of helium is 2 and the given symbol has two positive charge that represents loss of two electrons. So, the number of electrons in 
is 0.
Hence, has no electrons.
I think the correct answer would be D. The reaction that involves an acid and a covalent base would be the reaction of sulfuric acid and water or H2SO4 + 2H2O → 2H3O+ + SO42– . The acid would be H2SO4 and the covalent base would be H2O since it is being held by covalent bonds and when in solution it will have equal amounts of OH- and H+ ions.
Answer:
4.50 L
Explanation:
First we <u>calculate how many moles are there in 3.84 L of a 8.50 mol/L solution</u>:
- 3.84 L * 8.50 mol/L = 32.64 mol
Now, keeping in mind that
- Concentration = Mol / Volume
we can calculate the volume of a 7.25 mol/L solution that would contain 32.64 moles:
- Volume = Mol / Concentration
- Volume = 32.64 mol ÷ 7.25 mol/L
So we could take 4.50 L of the 7.25 mol/L solution and evaporate the solvent until only 3.84 L remain.
Changes in pH may not only affect the shape of an enzyme but it may also change the shape or charge properties of the substrate so that either the substrate connot bind to the active site or it cannot undergo catalysis. In geneal enzyme have a pHoptimum. However the optimum is not the same for each enzyme
