She just need to remember the conversion ratios. And it could be better to get everything in metres, the SI base unit.
1 angstrom = 0.0000000001 m = 1.0 x 10^-10 m
1 nm = 0.000000001 m = 1.0 x 10^-9 m
1 km = 1000 m = 1.0 x 10^3 m
1 μm = 0.000001 m = 1.0 x 10^-6 m
Scientific notation always has the first part between 1 and 10, 10 being exclusive, and a second number which indicates the 'order' so to say and has 10 raised to the power of an integer (whole) number.
For example:
1.0 x 10^-5 is correct.
0.976 x 10^2 is incorrect and should be 9.76 x 10^1
10.5 x 10^7 is incorrect and should be written as 1.07 x 10^8
How to change those is simple too. Take the second example:
0.976 x 10^2
You have to multiply the first number by 10 to get it in range of 1 and 10. You need a 10, take it from the second number:
0.976 x 10^1 x 10
You have to decrease the value of the power to do that and then you multiply the first and last numbers, to get 9.76 x 10^1.
Taking the third example:
10.5 x 10^7
You have to decrease the first number here. So, you can break it up like that:
1.05 x 10 x 10^7
This done, you can increase the power of 10, to give:
1.05 x 10^8
However, addition, subtraction, multiplication and division of such numbers is something she might find new.
Though I'm a little confused that your daughter suddenly got to grade 9 when she recently was in grade 7...