Beryllium has an atomic number of 4 and an atomic mass of 9. How many neutrons does Beryllium have?

Imagine if during the cathode ray experiment, the size of the particles of the ray was the same as the size of the atom forming the cathode. which other model or scientific observation would have also been supported? 1. this would support dalton's postulates that proposed the atoms are indivisible because no small particles are involved. 2. this would support bohr's prediction about electrons moving in orbits having specific energy. 3. this would support bohr's prediction about electrons being randomly scattered around the nucleus in the atom. 4. this would support dalton's postulates that proposed that atoms combine in fixed whole number ratios to form compounds.

Can someone check my work 98 5.05 acids and bases for this assignment you will be comparing acids and bases. the chart below will you organize the information needed: acids bases chemical properties (2) deodorant detergent vinger dish soap physical properties (2) orange juice toilet cleaner drain cleaner window cleaner ph level acid ph goes from 0-4 bases ph goes from 10-14 examples around you (2) vinger coffee lemon juice dark chocolate

What is the amount of energy for a photon that has a 125 cm wavelength