Calculating Graphite Quantities: Formulas and Methods Explained

[j.williams]

Homework Statement

I need to solve a task which requires to calculate the quantities of graphite. For instance, the particle amount per emission. I think my calculation may use the wrong method/ formula, but I do not know alternative right equation.

The data available:
graphite granularity: 6.3 um
graphite density: 2.23-2.29 (g/cm^3)
min. dispersion: 0.45 (kg/minute)

Homework Equations

I do not know any equation that can be directly applied to calculate the amount of particle. So I try alternative way as 3.

The Attempt at a Solution

Because the min dispersion is 0.45 (kg/minute) which equals to 0.0075 (kg/sec), resulting in 7.5 (g/s).

The density of graphite is between 2.23 (g/cm^3) ~ 2.29 (g/cm^3), so we use average value 2.26 (g/cm^3)

For graphite with density 2.26 (g/cm^3), achieving the weight 7.5 (g) would require volume 3.3185840707964601769911504424779 (cm^3) calculated by 7.5 / 2.26.

Also, 1 (cm^3) = 10^12 (um^3).

Therefore, 3.3185840707964601769911504424779 (cm^3) roughly equals to 3318584070796.4601769911504424779 (um^3).

Each graphite with diameter 6.3 (um) whose volume would be 250.047 (um^3).

So the quantities of graphite would be 13271841177.044556331374303400872 (3318584070796.4601769911504424779/ 250.047).

I understand this calculation may be completely wrong. So I would like to know 1.) if there is a right formula/ equation that can be applied to derive the right value with the data I have (if more information are required, what variables would need?), or 2.) if no such equation, with this attempt is it (13271841177.044) the right result (precision is not the most important issue, just want to be sure the logic is in the right direction)?

I appreciate any advice.

 

[SteamKing]

Say hello to significant figures. The original data you have given have at most 2 significant figures. Presenting calculated values like 13271841177.044556331374303400872 is way more precise than the original data, not to mention more cumbersome to manipulate.

 

[Borek]

I think the logic is OK, although you have hidden it behind too many digits.