How to round significant figures

Explanation:

To round to a significant figure:

look at the first non-zero digit if rounding to one significant figurelook at the digit after the first non-zero digit if rounding to two significant figuresdraw a vertical line after the place value digit that is requiredlook at the next digitif it's 5 or more, increase the previous digit by oneif it's 4 or less, keep the previous digit the samefill any spaces to the right of the line with zeros, stopping at the decimal point if there is oneHope it will help you

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na

No. an alpha particle is a pair of protons and a pair of neutrons, i.e. a helium