Answer:
The mass is recorded as 32.075 g
Explanation:
"The first digit of uncertainty is taken as the last significant digit", this is the rule for significant figures in the analysis. The balance measures the mass up to three decimal places, so it makes the most sense to note the whole figure.
We are tasked to solve for the volume of the gas that occupies when pressure and temperature changes to 400 Torr and 200 Kelvin from Torr and 400 Kelvin. We can use ideal gas law assuming constant gas composition and close system. The solution is shown below:
P1V1 / T1 = P2V2 / T2
V2 = P1V1T2 / T1P2
V2 = 800*72*200 / 400*400
V2 = 72 ml
The answer for the volume is 72 ml.
Answer:
4 g after 58.2 years
0.0156 After 291 years
Explanation:
Given data:
Half-life of strontium-90 = 29.1 years
Initially present: 16g
mass present after 58.2 years =?
Mass present after 291 years =?
Solution:
Formula:
how much mass remains =1/ 2n (original mass) ……… (1)
Where “n” is the number of half lives
to find n
For 58.2 years
n = 58.2 years /29.1 years
n= 2
or 291 years
n = 291 years /29.1 years
n= 10
Put values in equation (1)
Mass after 58.2 years
mass remains =1/ 22 (16g)
mass remains =1/ 4 (16g)
mass remains = 4g
Mass after 58.2 years
mass remains =1/ 210 (16g)
mass remains =1/ 1024 (16g)
mass remains = 0.0156g
Answer:
kindly check the EXPLANATION SECTION
Explanation:
In order to be able to answer this question one has to consider the neutron proton ratio. Considering this ratio will allow us to determine the stability of a nuclei. The most important rule that helps us in determination of stability is that when the Neutron- Proton ratio of any nuclei ranges from to 1 to 1.5, then we say the nuclei is STABLE.
Also, we need to understand that when the Neutron- Proton ratio is LESS THAN 1 or GREATER THYAN 1.5, then we say the nuclei is UNSTABLE.
So, let us check which is stable and which is unstable:
a. 4 protons and 5 neutrons = Neutron- proton ratio = N/P = 5/4= stable.
b. 7 protons and 7 neutrons = Neutron- proton ratio = N/P = 7/7= 1 = stable.
c. 2 protons and 3 neutrons = Neutron- proton ratio = N/P = 3/5 =0.6 =unstable.
d. 3 protons and 0 neutrons = Neutron- proton ratio = N/P = 0/3= 0= unstable.
e. 6 protons and 5 neutrons = Neutron- proton ratio = N/P = 5/6= 0.83 = unstable.
f. 9 protons and 9 neutrons = Neutron- proton ratio = N/P = 9/9 = 1 = stable.
g. 8 protons and 7 neutrons = Neutron- proton ratio = N/P = 7/8 =0.875 = unstable.
h. 1 proton and 0 neutrons = Neutron- proton ratio = N/P = 0/1 =0 = unstable
Answer:
The empirical formula of the solid metal oxide is : 
Explanation:
M atom is present in the every corner and in the center of every face.
Number of m atoms :

Number of tetrahedral voids in F.C.C = 2n = 2 × 4 = 8
Oxide ion is present in the half of the tetrahedral void
Number oxide ions = 
The molecular formula of the solid metal oxide is : 
The empirical formula represent the lowest number of atoms present in a compound.
The empirical formula of the solid metal oxide is : 