The last one would be false
The <span>molar concentration of the crystal violet solution is more concentrated than that of the sodium hydroxide solution. It is because the crystal violet solution has more solute in it compared to the sodium hydroxide.</span>
<span>A chemist adds 155.0ml of a 4.10 X 10^-5 mmol/L of a zinc oxalate (ZnC2O4)solution to a reaction flask. Calculate the mass in micrograms of zinc oxalate the chemist has added to the flask.
1mmol = 10^-3 mol
Therefore 4.10*10^-5mmol = 4.10*10^-8mol
molar mass ZnC2O4 = 65.39+(2*12.011)+(4*15.99) = 153.372g/mol
You have 4.10*10^-8 mol/litre =153.372 * 4.10*10^-8 = 6.29*10^-6 grams / litre (* see below)
But you have 155ml. Mass of ZnC2O4 = 155/1000*6.29*10^-6 g
Mass is = 9.75*10^-7 grams
1µg = 10^-6 g
You then have 9.75*10^-7/10^-6 = 0.975µg ZnC2O4
(*see below) at this point you could have said:
1µg = 10^-6 g therefore you have a solution of 6.29µg per litre,
155ml = 6.29*155/1000 = 0.975µg ZnC2O4</span>
The element is Sodium with an atomic number of 11 and electrovalent bonding takes place when it comes near an atom having seven valence electrons.
<h3>What is Electrovalent bonding?</h3>
This is also referred to as ionic bonding and involves the transfer of atoms of an element to another.
In order for both of them to achieve a stable octet configuration, sodium donates one atom to the element seven valence electrons.
Read more about Electrovalent bonding here brainly.com/question/1979431
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Answer:
oxidation
Explanation:
oxidation number are based on the distribution of electrons in a molecule