The parent isotope percent will change from 100% to 50% to 25% to 12.5% and to 6.25%. So the sample go through four times of half-life. So the sample is 58*4=232 years old.
Answer:
nitrogen 18
nitrogen has an atomic number of 7
This is an incomplete question, here is a complete question.
Calculate the volume in milliliters of a 1.29 mol/L iron(II) bromide solution that contains 275 mmol of iron(II) bromide . Round your answer to significant 3 digits.
Answer : The volume of iron(II) bromide solution is, 
Explanation : Given,
Concentration of iron(II) bromide = 1.29 mo/L
Moles of iron(II) bromide = 275 mmol = 0.275 mol
conversion used : 1 mmol = 0.001 mol
Now we have to calculate the volume of iron(II) bromide.

Now put all the given values in this formula, we get:

Thus, the volume of iron(II) bromide solution is, 
Answer:
c. fluorine
Explanation:
A single replacement reaction is defined as the chemical reaction in which a strong molecule replaces the weak molecule from a compound.
In a single replacement reaction, the chloride ion in NaCl can be replaced by fluorine and gives Sodium fluoride as fluorine (F) is stronger than chlorine (Cl) and from other given molecules also. So the single replacement reaction between NaCl and F will be:
NaCl + F2 => NaF + Cl2
Hence, the correct answer is "c. fluorine".
Answer:
Remove your shirt and any other clothing that were in contact with the chemical
Explanation:
A hazardous chemical has the capacity to cause damage to the body when it comes in contact with the skin. Many hazardous chemicals are capable of being absorbed into the body via the skin.
Once your lab coat is already doused with the chemical and it has started soaking into you clothing, you must remove your lab coat, shirt and all clothing that were in contact with the hazardous chemical as a safety measure to avoid absorption of the chemical into the body via the skin. Some of these chemicals also cause damages directly to the skin and this must be avoided.