Answer: protons and neutrons.
The nucleus is made up of 3 subatomic particles that are protons,neutrons and electrons.
General notation of an element is 
where, X is the Element, A is the Atomic Mass and Z is the Atomic Number
If we know the number of protons we can easily find out the atomic number of any element because Atomic Number = Number of protons in an element.
And in addition if we know the number of neutrons we can easily find out the atomic mass of an element because
Atomic Mass = (Number of protons) + (Number of neutrons)
If we get to know the atomic number and atomic mass, we can easily tell what element is it by looking from the periodic table.
Answer:
The digestive system uses mechanical and chemical methods to break food down into nutrient molecules that can be absorbed into the blood. ... Some animals use intracellular digestion, where food is taken into cells by phagocytosis with digestive enzymes being secreted into the phagocytic vesicles.
Explanation:
Answer:
Pu-239
Explanation:
Beta decay moves the element which undergoes the decay one place to the right in the periodic table since to conserve charge and being beta radiations an electron we convert a neutron into a proton and an electron. In neutron capture we increase the atomic mas by one unit. We that in mind, lets solve the question:
U-238 + ₁⁰ n ⇒ U-239 ⇒ Np -239 + ₋₁⁰β ⇒ Pu-239 + ₋₁⁰β
The given question is incomplete. The complete question is :
It takes 151 kJ/mol to break an iodine-iodine single bond. Calculate the maximum wavelength of light for which an iodine-iodine single bond could be broken by absorbing a single photon. Be sure your answer has the correct number of significant digits.
Answer: 793 nm
Explanation:
The relation between energy and wavelength of light is given by Planck's equation, which is:

where,
E = energy of the light = 151 kJ= 151000 J (1kJ=1000J)
N= moles = 1 = 
h = Planck's constant = 
c = speed of light = 
= wavelength of light = ?
Putting in the values:


Thus the maximum wavelength of light for which an iodine-iodine single bond could be broken by absorbing a single photon is 793 nm