20 minutes.
The sample would lose one half the quantity of francium in each half-life.
Thus a mass decrease by a factor of 16 would correspond to a period of four half-lives. It took 80 minutes for the sample to lose all these francium, therefore
minutes.
Answer: a magnet force changes the compass movement
Explanation:
<span>The notation of the isotopes using the atomic number and the mass number consists of the symbol of the atom, preceded by the mass number as a superscript and the atomic number as a superscript.
All the isotopes of the same element have the same atomic number. They only vary the mass number.
So, all the isotopes of oxygen have atomic number 8.
The isotope oxygen-16 has mass number 16, so it is written with the symbol O preceded by the number 16 as a superscript and the number 8 as a subscript (the two numbers to the right of the chemical symbol).
The isotope oxygen-17 has mass number 17, so it is written with the symbol O preceded by the number 17 as a superscript and the number 8 as a subscript.
The isotope oxygen-18 has mass number 18, so it is written with the symbol O preceded by the number 18 as a superscript and the number 8 as a subscript.</span>
A single replacement reaction can be represented by the equation AB + C = AC + B
Answer:
a. C > F > Cl
Explanation:
We know that atomic mass of Chlorine is greater than of Florine than that of carbon. Moreover, in CF2Cl2, therefore, there are two atoms of Cl, F and one atom of C. Therefore, in CF2Cl2 in order of decreasing mass percent composition C > F > Cl. Therefore, the correct option is a.
