How does periodic table summarize what we know about elements?

Why does the sun seen to rise and set

A potato contains 20 g of carbohydrate. if carbohydrate has a caloric value of 4 kcal/g, how many kcal are obtained from the carbohydrate in the potato?

2 Which particle has a mass of approximately 1 atomic mass unit? (1) an alpha particle (3) an electron (2) a beta particle (4) a neutron

One example of a decomposition reaction is the electrolysis of water. the chemical reaction can be expressed by the equation 2 h2o →2 h2 o2. the reactant (s) of this chemical reaction is/are?

Choose the correct equation to represent the following statement (unbalanced chemical equation): Aluminum reacts with hydrochloric acid to yield aluminum chloride and hydrogen. A. AlCl3 + H2 Al + HCl B. Al + HCl AlCl3 + H2 C. Al HCl + AlCl3 + H2 D.

Which experimental feature of the MALDI-MS technique allows the separation of ions formed after the adduction of tissue molecules? A) Distance travelled by ions depends on the ion charge. B) Velocity of ions depends on the ion mass-to-charge ratio.

Which temperature is required for the cell potential to be the standard cell potential? A) - 273°C B) 100°C C) 25°C D) 0°C

1. the purpose of the aqueous solutions in a galvanic cell is to? a. provide ions to be oxidized and reduced b. provide a path for the free flow of electrons c. maintain charge balance in the cell d. correct any volume changes in the cell 2.

A. Identify which of the following substances dissolve in water, explaining why for each example: CH4, He, MgSO4, NaHCO3 b.

Hydrogen is a pure substance represented by the chemical symbol h. which of the following best describes hydrogen a. hydrogen is a compound made of only one kind of atom. b. hydrogen is a compound made of two or more kinds of atoms. c.