How many protons and electrons are each contained in an atom of element number 44?

How can you describe the location of hafnium (Hf, atomic number 72) on the periodic table? Choose all that apply. (A) Transition metals (B) Noble gases (C) Group 6, Period 4 (D) Group 4, Period 6

Is it true that polyphonic ions always carry a positive charge?

What speeds up a chemical reaction

What is the frequency (in reciprocal seconds) of electromagnetic radiation with a wavelength of 1.07 cm?

1.) Which is the correct order of the organization of the human body? A.) Cell-tissue-organ-organ system-organism B.) Cell-organ-system organ-tissue-organism C.) Tissue-organ-cell-organ system-organism D.) Organ-organ system-tissue-cell - organism 2.

There are seven major levels of classification. Kingdom and Phylum are just two of the levels. Which of the following are also major levels of classification? Choose all answers that are correct. A. Class B. Order C. Family D. Level

An experiment with high validity is

What is the smallest part of a tree that can do all the things needed for life?

As the PH scale decreases or increases, how does this affect the acidity?

During an endothermic phase change, what happens to the potential energy and the kinetic energy? Potential energy stays the same, and kinetic energy increases. Potential energy increases, and kinetic energy increases.