Answer:
lol thanks for the point btws! i really needed them for my math test questions have a good day btw! good vibes!
Explanation:
Answer:
It would be an isotope.
Background Information:
Isotopes are typically elements that have a different number of protons than neutrons. The atomic mass is the total number of protons and neutrons. The atomic number is the number of protons.
Explanation:
If the atomic number is the number of protons that means that this particular element has 8 protons. If the atomic mass is the total number of protons and neutrons then we can simply take away the amount of protons from that number, 18 - 8 = 10. If we take protons away from the number of protons and neutrons we are left with the number of neutrons. So there are 10 neutrons. Because there are 8 protons and 10 neutrons, or a different amount of neutrons and protons we know that this particular atom is an isotope.
Answer:
- <em>The mystery substance is</em> <u>C. Bromine (Br) </u>
Explanation:
<em>Argon (Ar) </em>is a noble gas. Whose freezing point is -189 °C (very low), thus it cannot be the frozen substance. Also, it is not reactive, thus is would have not reacted with iron. Hence, argon is not the mystery substance.
<em>Scandium (Sc) </em>is a metal from group 3 of the periodic table, thus is will not react with iron. Thus, scandium is not the mystery substance.
Both <em>bromine</em> and <em>iodine</em> are halogens (group 17 of the periodic table).
The freezing point of bromine is −7.2 °C, and the freezing point of iodine is 113.7 °C. Thus, both could be solids (frozen) in the lab.
The reactivity of the halogens decrease from top to bottom inside the group. Bromine is above iodine. Then bromine is more reactive than iodine.
Bromine is reactive enough to react with iron. Iodine is not reactive enough to react with iron.
You can find in the internet that bromine vapour over hot iron reacts producing iron(III) bromide. Also, that bromine vapors are red-brown.
Therefore, <em>the mystery substance is bromine (Br).</em>
Answer:
t=(70)ln(19.9/20)/-ln2
70 is the years. 19.9 kg is what is left after 0.1kg decay. 20kg is your initial amount.
t=0.506 years with a decay constant of 0.0099021/year
Explanation:
