Answer:
115g/mol
Explanation:
To get the molar mass, we know that the it is equal to the mass divided by the number of moles. We have the mass but we do not have the number of moles.
We get this by working through the solution information. Firstly, we need to know the number of moles in 750ml for a molarity of 0.29m
Now, since 0.29 moles is present in 1000ml, x moles will be present in 750ml
The value of x is obtained as follows:
x = (750 * 0.29)/1000 = 0.2175 moles
Now since we have the number of moles, we can then obtain the molar mass.
Molar mass = mass/number of moles = 25.0g/0.2175 = 114.94 approximately 105g/mol
The options
Select one:
a. a 3- ion forms.
b. the noble gas configuration of argon is achieved.
c. the result is a configuration of 1s2 2s2 2p6.
d. the atom gains five electrons.
Answer:
c. the result is a configuration of 1s2 2s2 2p6.
Explanation:
Aluminium atom has atomic number of 13 , hence the number of electron is 13 for a neutral atom of aluminium. When aluminium atom reacts with other elements it usually gives out three electron to attain the octet configuration.
The cation representation of aluminium is Al3+ because it has loss three electron to attain the octet rule. Aluminium will be left with 10 electrons after losing 3 of it electrons. The electronic configuration will be represented as follows after losing three electrons;
1S² 2S² 2P∧6 .
At this stage the octet rule has been achieved as it will be represented as
2 8. The first energy shell now contains two electron and the second energy shell contains 8 electrons.
The configuration of Neon has been formed in the process.
Answer:
7.98 × 10^3grams.
Explanation:
To find the mass of fluorine in the number of atoms provided, we first divide the number of atoms by Avagadros number (6.02 × 10^23atoms) to get the number of moles in the fluorine atom. That is;
number of moles (n) = number of atoms (nA) ÷ 6.02 × 10^23 atoms
n = 2.542 × 10^26 ÷ 6.02 × 10^23
n = 0.42 × 10^ (26-23)
n = 0.42 × 10^3
n = 4.2 × 10^2moles
Using mole = mass ÷ molar mass
Molar/atomic mass of fluorine (F) = 19g/mol
mass = molar mass × mole
Mass (g) = 19 × 4.2 × 10^2
Mass = 79.8 × 10^2
Mass = 7.98 × 10^3grams.
An object that is not already moving will begin to move in the direction of the larger force. An object that is already moving will change its speed and/or its direction.
The mass of electrons, protons, and neutrons:
electrons 9.10938291*10^-31 kg
protons 1.67262178*10^-27 kg
neutrons 1.6749*10^-27 kg
the mass of electrons is way smaller than both, the mass of protons and neutrons
therefore, 1) the mass of 2 electrons is the smallest