KE = mv²/2
m=2*KE/v²
v=50 m/s
KE=500J
m=2*KE/v² =2*500/50²=1000/2500= 0.4 kg
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
Answer:
[Ne] 3s² 3p²
Explanation:
Silicon atoms have 14 electrons. The ground state electron configuration of ground state gaseous neutral silicon is 1s²2s²2p⁶3s²3p².
Using noble gas shorthand, the electronic configuration is reduced to;
[Ne] 3s² 3p². Ne s the nearest noble gas to silicon, Ne contains 8 electrons, this means there's still 4 more electrons to fill. The s orrbital can only hold 2, hence the reaing two is transferred to the p orbital.
Explanation:
Formula to calculate osmotic pressure is as follows.
Osmotic pressure = concentration × gas constant × temperature( in K)
Temperature = 
= (25 + 273) K
= 298.15 K
Osmotic pressure = 531 mm Hg or 0.698 atm (as 1 mm Hg = 0.00131)
Putting the given values into the above formula as follows.
0.698 = 
C = 0.0285
This also means that,
= 0.0285
So, moles = 0.0285 × volume (in L)
= 0.0285 × 0.100
= 
Now, let us assume that mass of 
= x grams
And, mass of 
= (1.00 - x)
So, moles of 
= 
Now, moles of 
= 
= 
= x = 0.346
Therefore, we can conclude that amount of present is 0.346 g and amount of 
present is (1 - 0.346) g = 0.654 g.
Answer:
6.02 x 10²³ atoms
Explanation:
Given parameters:
Number of moles CaSO₄ = 1 mole
Unknown:
Number of Ca atoms in the given compound = ?
Solution:
The given compound is:
CaSO₄
1 mole of CaSO₄ is made up of 1 mole of Ca atoms
Now;
1 mole of any substance contains 6.02 x 10²³ atoms
1 mole of Ca atoms will also contain 6.02 x 10²³ atoms
