Answer:
Explanation:
There are 118 different known <em>elements</em>.
Each element is identified by the number of protons and it is called the atomic number. For instance, the atomic number of hydrogen is 1, every hydrogen atom has one proton; the atomic number of oxygen is 8, every oxygen atom has 8 protons; the atomic number of carbon is 6, every carbon atom has 6 protons.
There are not two different elements with the same atomic number (number of protons).
The 118 known elements are listed in the periodict table in groups (columns) and periods (rows) in increasing order of atomic number (number of protons).
So, by counting the number of protons of an atom, chemists can tell the element to which the atom belong.
Answer:
4.43L is final volume of the ballon
Explanation:
Avogadro's law of ideal gases states that <em>equal volumes of gases, at the same temperature and pressure, have the same number of molecules</em>.
The formula is:

Where V and n are volume and moles of the gas in initial and final conditions.
If the initial conditions are 0.0145 moles and 2.54L and final amount of moles is 0.0253moles, final volume is:

V₂ = <em>4.43L is final volume of the ballon</em>
The relation between °C and °F is
°F=
5
9
(°C)+32
when °F=°C
∴°C=
5
9
°C+32
∴°C−
5
9
°C=32
∴−
5
4
°C=32
∴°C=−40°C
∴T=−40℃
∴ At −40℃, both the celcius and Fahrenheit scales show the same reading.