How many protons are in Se-2?

When aluminum is placed in concentrated hydrochloric acid, hydrogen gas is produced. what volume of h2 is produced when 7.20 g of al reacts at stp?

Although electrons have mass, they are not considered in determining the mass number of an atom. Why?

Correctly identify the generic formula for a synthesis reaction. a. AB + A+B b. A+B → AB c. CxHx + O2 → CO2 + H2O d. AB + C + AC + B e. AB + CD → AD + CB

A cube has a depth of 10 cm. What is the volume of the cube? Or What is depth?

An example of an adaptation that gives an organism greater access to energy

The volume of 1 mole of o2 gas at T=273k P=1atm is? A 6.02 x 10^-23 ml B 760 L C 22.4 L D 2.24 L E 224 L

There are two stable isotopes of bromine. Their masses are 78.9183 and 80.9163 amu. If the average atomic mass of bromine is 79.9091 amu, what is the natural abundance of the heavier isotope? percent abundance of 81Br __%

If 1.00 mol of argon is placed in a 0.500-L container at 20.0 ∘C, what is the difference between the ideal pressure (as predicted by the ideal gas law) and the real pressure (as predicted by the van der Waals equation) ? For argon, a=1.

Which of these is a covalent compound? 1. AICI3 2. CO 3. MgO 4. LiCI

What is a protein used for