Answer:
Atoms: <em>they are tiny particles that are the basic building blocks of any substance. The atoms are themselves made up of even smaller particles-protons, neutrons and electrons. </em>
Molecules: <em>it is the smallest unit of matter, which can exist independently. A molecule is formed when two or more atoms combine together.</em>
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<em>hope it helps</em>
<em>and ur welcm</em>
<em>:)</em>
A. The mass of one mole of the virus is calculated by multiplying the mass of a single virus by the Avogadro's number which is equal to 6.022 x 10^23. Performing this operation,
mass = (9.0 x 10^-12 mg)(6.022 x 10^23) = 5.42 x 10^12 mg
In correct number of significant figures, the answer would only have to be 5.4 x 10^12 mg.
b. The number of moles of the virus that will have the same mass as the oil tanker is calculated by dividing the mass of the oil tanker by the mass of one mole of the virus. Note that doing division, both would have to have the same units.
n = (3.0 x 10^7 kg) / (5.4 x 10^12 mg)(1 g/1000 mg)(1 kg/1000 g)
Simplifying,
n = 6
In correct number of significant figures, the answer is 6.0.
A cation is smaller than its parent atom.
Therefore, here a sodium ion is smaller than the neutral sodium atom.
Reason: Since the sodium atom loses an electron to form an electropositive ion(cation), its nuclear charge increases(the number of protons exceeds the number of electrons) and the orbital electrons are pulled with a greater energy.
Thus,the sodium ion shrinks in size.
Answer:
THE TEMPERATURE AT WHICH THE CHEMICAL REACTION IS BEING CONDUCTED.
Explanation:
The reaction rate constant is dependence on the temperature in which the reaction takes place. The rate of a reaction and the activation energy relationship is given by the Arrhenius equation with the rate constant as a function of temperature.
Mathematically, the rate constant is expressed as;
k(T) = Ae^-Ea/RT
where Ea is the activation energy, R is the gas constant, Ae is the pre-exponential factor and it is the frequency at which a reactant molecule collide with each other, T is the temperature.
Answer:
<u>One lone-Pair is present in Ammonia</u>
<u></u>
Explanation:
The number of valence electron in N = 5
The number of Valence electron in H = 1
The formula of ammonia = NH3
Total valence electron in ammonia molecule = 5 +3(1) = 5+3 = 8
The lewis structure suggest that :
Nitrogen completes its octet by sharing the electron pair with 3 hydrogen atoms.
3 electron of Nitrogen are involved in sharing with Hydrogen
So,<u><em> remaining two electron are left non-bonded</em></u> . Hence they exist as lone- pair
So, there is only 1 lone pair in the ammonia molecule .
The shape of NH3 is bent according to VSEPR theory . This is so because the presence of 1 lone pair causes more repulsion and occupy more space.
Thus the lone pair is changing the shape of the ammonia molecule . It also increase the dipole moment of the molecule , which gives polarity to it.
