How does the number of valence electrons for elements change across a period?

The number decreases.

The number increases.

The number stays constant.

The number increases and then decreases for noble gases

Com: if a protein contains 150 amino acids, there would be how many codons in the specification to construct it?

What can be said about this equation? 2Na (s) + Cl2 (g) → 2NaCl (s)

Antimycin A blocks electron transfer between cytochromes b and c1. If intact mitochondria were incubated with antimycin A, excess NADH, and an adequate supply of O2, which of the following would be found in the oxidized state?

What does the prefix hepta mean

If 27.5 mL of 16.0 M nitric acid stock solution is added to 300. mL of water, what is the molarity of the diluted solution?

Which would exhibit characteristics of both a metal and a nonmetal? select one: a. si b. ge c. sb d. po e. all of the above exhibit characteristics of both a metal and a nonmetal?

In the synthesis reaction, the white powder produced is magnesium oxide (mgo, mm = 40.3 g/mol). how many moles of magnesium oxide were formed (number of moles = mass (g) / molar mass (g/mol)) ? choose the closest answer. a. 0.21 moles b. 0.

Which of the following is the most likeley example of an favorable mutation A. A mutation that makes a rabbit able run faster B. A mutation that changes the rabbit's fur to bright orange C. A mutation that changes the color of the rabbit's eyes D.

Which of these mole ratios is possible for this reaction? FeCl3 + 3NaOH → Fe (OH) 3 + 3NaCl 1:1 1:3 3:1 2:3

The chemical equation for reduction of phosphorite Ca3 (PO4) 2