•3.9g of ammonia
•molar mass of ammonia = 17.03g/mol
1st you have to covert grams to moles by dividing the mass of ammonia with the molar mass:
(3.9 g)/ (17.03g/mol) = 0.22900763mols
Then convert the moles to molecules by multiplying it with Avogadro’s number:
Avogadro’s number: 6.022 x 10^23
0.22900763mols x (6.022 x 10^23 molecs/mol)
= 1.38 x 10^23 molecules
That is called condensation
Answer:
A. there is an isotope of lanthanum with an atomic mass of 138.9
Explanation:
By knowing the different atomic masses of both Lanthanum atoms, we can not tell anything about their occurence in nature. Therefore, all the last three options are incorrect. Because, the atomic mass does not tell anything about the availability or natural abundance of an element.
Now, the isotopes of an element are those elements, which have same number of electrons and protons as the original element, but different number of neutrons. Therefore, they have same atomic number but, different atomic weight or atomic masses.
Hence, by looking at an elements having same atomic number, but different atomic masses, we can identify them as isotopes.
Thus, the correct option is:
<u>A. there is an isotope of lanthanum with an atomic mass of 138.9.</u>
Answer:
35.5g of sugar
Explanation:
To solve this question we must assume the density of coke = Density of water = 1g/mL
Thus, in a single can of coke, the mass is 355g. Now, the 10% of this coke is sugar. That means the amount of sugar you are consuming is:
355g * (10/100) = 35.5g of sugar
<em>10/100 = 10%</em>
Answer:
Specific heat is defined as the amount of heat needed to raise the temperature by one degree celsius. Therefore, in 1 kg there are 100 grams so, 10 grams equal 0.01 Kg. Thus, calculate the specific heat value as follows. Thus, we can conclude that specific heat of the given metal is 0.5 .
Explanation:
