Answer:
d and e - Sodium and antimony
Explanation:
The atomic numbers remain the same, while the mass numbers change (because neutrons are being added or taken away).
sodium has an atomic number of 19 and a mass number of 39 - in d, it has an atomic number of 19 but a mass number of 40. therefore, it is an isotope
antimony has an atomic number of 51 and a mass number of 121.60 - in e, it has an atomic number of 51, but a mass number of 123. therefore, it is an isotope
Answer:
elements are composed of
electrons with a little mass and negative charge
protons with mass and positive charge
neutrons with mass and no charge
isotopes same number of protons, different in neutrons
share me the other part of the photo to complete!!!
Im not really sure what your asking.... <span>Standard sea-level pressure, by definition, equals 760 mm (29.92 inches) of mercury, </span>14.70 pounds per square inch<span>, 1,013.25 × 10 </span>3<span> dynes per square centimetre, 1,013.25 millibars, one standard atmosphere, or 101.325 kilopascals.
</span><span>""atmospheric pressure | Britannica.com""</span>
We are given with the initial volume of the substance and the molarity. The first thing that needs to be done is to multiply the equation in order to obtain the number of moles such as shown below.
number of moles = (40 mL) x (1 L / 1000 mL) x (0.3433 moles / L)
number of moles = 0.013732 moles
To get the value of the molarity of the diluted solution, we divide the number of moles by the total volume.
molarity = (0.013732 moles) / (750 mL / 1000 mL/L) = 0.0183 M
Similarly, we can solve for the molarity by using the equation,
M₁V₁ = M₂V₂
Substituting the known values in the equation,
(0.3433 M)(40 mL) = M₂(750 mL)
M₂ = 0.0183 M