12, if the decimal is over five, round up. If it's not, round down. Not sure what you mean by significant figures.
It is the work of J.J Thomson that directly resulted in the development of an atomic model that has negative electrons stuck within a sea of positive material. His proposal was called the plum pludding model. He is the one who discovered electrons.
Hey there!
The number of vacancies per unit volume => ( Nv = 2.3*10²⁵ m⁻³ )
Avogrado's number => ( NA = 6.022*10²³ atoms/mol )
Density of material ( p ) in g/m³ :
1 g/cm³ = 1000000 g/m³ so:
7.40 * ( 1000000 ) = 7.40*10⁶ g/m³
Atomic mass = 85.5 g/mol
* Calculate the number of atomic sites per unit volume :
N = NA * p / A
N = ( 6.022*10²³ ) * ( 7.40*10⁶ ) / 85.5
N = 4.45*10³⁰ / 85.5
N = 5.212*10²⁸ atoms/m³
Therefore:
Calculate the fraction of vacancies :
Fv = Nv / N
Fv = 2.3*10²⁵ / 5.212*10²⁸
FV = 4.441*10⁻⁴
Hope that helps!
Answer : The mathematical equation used when solving calorimetry problems is:
Explanation :
Calorimetry : It is determining the changes in the energy of a system by measuring the heat transferred with surroundings.
Formula used :
where,
c = specific heat capacity of calorimeter
m = mass of a substance
q = heat required
= change in temperature of substance
Answer:
50mL
Explanation:
Using Boyle's law equation as follows:
P1V1 = P2V2
Where;
P1 = initial pressure (torr.)
P2 = final pressure (torr.)
V1 = initial volume (mL)
V2 = final volume (mL)
According to the information provided in the question,
V1 = 25.0mL
V2 = ?
P1 = 760 torr.
P2 = 380 torr.
Using P1V1 = P2V2
V2 = P1V1//P2
V2 = (760 × 25) ÷ 380
V2 = 19000 ÷ 380
V2 = 50mL
