Why is it necessary for the measuring devices to be clean

I know there are 4.5*10^-9 seconds in 4.5 nanoseconds, but when I enter it into my TI-30xIIs, I get 4.5*10^-10. I enter it as 4.5 * (1/10^9) in my calculator ... what am I doing wrong?

Which of the following is not a type of radiation? A. trans-radiation B. inhaled radiation C. terrestrial radiation D. cosmogenic radiation

Why might someone write their postcode on a tv or computer using a pen with fluorescent ink that is not visible in normal light?

How would you balance the following equation NaOh + H2CO3=Na2CO3+H2O?

Write a balanced equation for the combination reaction described, using the smallest possible integer coefficients. When diphosphorus pentoxide combines with water, phosphoric acid is formed.

A conical, flat-bottomed flask with a narrow neck that can be used for heating, mixing, watching reactions, and swirling, not for measuring

Answer 1. the law of conservation of mass states that mass is neither created nor destroyed in an ordinary chemical reaction. when an iron nail rusts, it seems to get heavier in mass. does the iron nail follow the law of conservation of mass?

Ammonia (NH3) burns in air to form nitrogen dioxide and water. Calculate grams of nitrogen dioxide produced if 4.0 grams of ammonia are consumed

What year did mendeleev organized his periodic table in order of increasing atomic number

What is the volume of 1.9 moles of chlorine gas (Cl2) at standard temperature and pressure (STP) ? 12 L 22.4 L 43 L 81 L