In order to determine the number of molecules of nitrogen dioxide that are in 1.28 g of nitrogen dioxide, we first need to know these values:
Molar mass of nitrogen dioxide = 46.0055 g/mol
Avogadro's number = 6.022 x 10^23 molecules/mol
Then, we divide 1.28 g by the molar mass and multiply the resulting value to Avogadro's number:
1.28 g/ 46.0055 g/mol x 6.022 x 10^23 molecules/mol = 1.6755 x 10^22 molecules of nitrogen dioxide
density of the object = 0.53 g/mL
Explanation:
First we need to find the volume of the object which is equal to the rise of the water in the graduated cylinder:
volume = 31.7 - 25.1 = 6.6 mL
Now we calculate the density of the object using the following formula:
density = mass / volume
density = 3.5 g / 6.6 mL
density = 0.53 g/mL
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density
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In a neutral ion, the number of protons would be equal to the number of electrons. You get a positive or negative charge when electrons are lost or gained.
Example: 12/6 C1-
There are 6 protons, 6 neutrons, and 7 electrons.
Answer:
2.01
Explanation:
First, let's convert grams to moles
(Na) 22.99 + (F) 18.998 = 41.988
Every mole of NaF is 41.988 grams
21/41.988 = 0.500143 moles of NaF
For every Cr+3, we will need 2 NaF, so Cr+3 will be half of NaF
0.500143/2 = 0.250071
molarity = moles/liters
0.250071/0.125 = 2.0057 M
