Is a candle melting in the hot sun a chemical or a physical change?

Given that the molar mass of nano3  is 85.00  g/mol, what mass of nano3  is needed to make 4.50  l of a 1.50  m nano3solution? use  .6.75 g18.9 g255 g574 g

Naoki's bicycle has a mass of 10 kg. if naoki sits on her bicycle and starts pedaling with a force of 168 n, causing an acceleration of 2.8 m/s2, what is naoki's mass?

What is the most stable monatomic ion formed from nitrogen