Answer:
given that
....the mass of the metal is 20g(0.02kg)
....specific heat capacity(c) is 0.4J/g°C
....ΔT=??
heat(Q)=3.9KJ(3900J)
Q=mcΔT
ΔT= Q/mc
.....=3900÷(20g x 0.4J/g°C)
.....=487.5°C
Im dying at the fact that you put in under ‘Chemistry’, good luck though.
When you change the number of protons in an atom, you will change the atom from one element to a different element. Sometimes, when you add a proton to an element, the element will become radioactive. If you change the number of electrons in an atom, you will get an ion of the element.
The elements are listed in order of increasing the atomic number. Its the number that is the number of protons in the nucleus of an atom.
Strontium element has a mass number of 88 and contains 50 neutrons in the atom.
Given that;
Mass number of element X = 88
Number of Neutrons in element X = 50
we know the concept that Mass number is represent as total number of Neutrons and proton present in Nucleus
So, Mass number of element X = Number of Neutrons in element X + Number of Protons in element X
Thus, 88 = 50 + Number of Protons in element X
Number of Protons in element X = 38
As, Number of proton = Atomic number
So, Atomic number of element X = 38
Hence Unknown Element X is Strontium
To know more about Strontium element visit here ; brainly.com/question/19298437?referrer=searchResults
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