Atomic mass Calcium = 40.078 a.m.u
40.078 g ---------------- 6.02x10²³ atoms
165 g -------------------- ??
165 x ( 6.02x10²³) / 40.078 => 2.47x10²⁴ atoms
hope this helps!
Answer:
0.444 mol/L
Explanation:
First step is to find the number of moles of oxalic acid.
n(oxalic acid) = 
Now use the molar ratio to find how many moles of NaOH would be required to neutralize 
of oxalic acid.
n(oxalic acid): n(potassium hydroxide)
1 : 2 (we get this from the balanced equation)
: x
x = 0.0111 mol
Now to calculate what concentration of KOH that would be in 25 mL of water:
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:
M = 20.5 g/mol
Explanation:
Given data:
Volume of gas = 1.20 L
Mass of gas = 1.10 g
Temperature and pressure = standard
Solution:
First of all we will calculate the density.
Formula:
d = mass/ volume
d = 1.10 g/ 1.20 L
d = 0.92 g/L
Now we will calculate the molar mass.
d = PM/RT
0.92 g/L = 1 atm × M / 0.0821 atm.L/mol.K ×273.15 K
M = 0.92 g/L × 0.0821 atm.L/mol.K ×273.15 K / 1 atm
M = 20.5 g/mol
Answer:
The answer to that question would be A
Explanation:
