A stable isotope has just<em> the right number of neutrons for the number of protons </em>(the <em>n:p ratio</em>) to hold the nucleus together against the repulsions of the protons.
A radioactive isotope has either too few or too many neutrons for the nucleus to be stable,
The nucleus will then emit <em>alpha, beta, or gamma radiation</em> in an attempt to become more stable.
Answer:

Explanation:
mass of Fe = 55.85 g
Molar mass of Fe = 55.85 g/mol
<u>Moles of Fe = 55.85 / 55.85 = 1</u>
mass of Cl = 106.5 g
Molar mass of Cl = 35.5 g/mol
Moles of Cl = 106.5 / 35.5 = 3
Taking the simplest ratio for Fe and Cl as:
1 : 3
The empirical formula is = 
Answer:
1 x 10^-4
Explanation:
Use the equation pH = -log[OH-}
Rearranging it [OH-] = 10^-pH
Plugging in we get [OH-] = 1 x 10^-4
Salt water is considered to be a solution
Answer:
<em>This type of error affects overall accuracy but does not necessarily affect precision.</em> - Systematic error
<em>This type of error affects precision but does not necessarily affect overall accuracy.</em> - Random error
<em>This type of error occurs if you use a buret that was calibrated incorrectly when it was made.</em> - Systematic error
<em>You can minimize this type of error by taking repeated measurements.</em> - Random error
Explanation:
<em>Systematic errors are errors that are attributable to instrument being used during measurement or consistent incorrect measurement during a research</em>. They are consistently and repeatedly committed during measurements and therefore affect the overall accuracy of measurements. A person committing systematic error can have precise repeated measurement but will be far from being accurate.
R<em>andom errors on the other hand has no pattern and are usually unavoidable because they cannot be predicted.</em> When sufficient replicate measurements are made, such errors are reduced to the barest minimum and usually do not affect the overall accuracy of measurements.