A neutral atom of beryllium (Be) has an average mass of 9 amu and 4 electrons. How many neutrons does it have?

13

9

5

4

In the stratosphere, oxygen (o2) is converted to ozone (o3) by high energy ultraviolet light. when the equation is written and balanced using whole number coefficients, the coefficient of ozone is 1. 4. 2. 3.

What is the law of conservation of mass? how is it related to balancing chemical equations

What volume (in microlitres) of a 200M stock solution of a primer (molecular weight = 7.3 kDa) would you need to include in a 100ul PCR reaction to achieve a final concentration of primer of 300nM?

The 3 in 4p3 represents: a. third energy level b. the number of electrons c. period 3 d. the third sub level e. Li

The vapor pressure of 25 milliliters of water at 25 degrees celcius will be the same as

Calculate the percent composition of the compound that forms when 222.6 g N combines completely with 77.4 g 0. calculate to the nearest tenth of a percent.

How many moles of hcl will react with 450 mg of Al (OH) 3

Why are two nonpolar substances able to dissolve in each other?

Which of the following illustrates the conservation of matter? A. SnO2 + H2 - -> Sn + 2 H2O B. 2 C + O2 - -> CO2 C. KOH + HBr - -> KBr + H2O D. 6 Cs + N2 - -> 6 Cs3N I want to say B?

AIDS is caused by?