Niels bohr Study guides, Class notes & Summaries

CLEP Chemistry Latest Update Graded A John Dalton Proposed that matter is composed of atoms; these atoms have different identities called elements, which combine to form compounds; measured masses of reactants and products. J.J. Thompson Observed deflection of particles in a cathode ray tube; proposed that atoms are composed of positive and negative charges; developed the plum pudding model of the atom Robert Millikan Calculated the charge-to-mass ratio of electrons using oil drops falling in ...

MULTIPLE CHOICE 1. The term “atom” was first used by the ___________. a. Ethiopians b. British c. Greeks d. Romans ANS: C The term “atom” was first used by the Greeks DIF: Moderate REF: p. 27 OBJ: Relate the history of the term “atom.” 2. The first person to describe an element as being composed of identical atoms was __________. a. J. J. Thomson b. John Dalton c. Dmitri Mendeleev d. Niels Bohr ANS: B The first person to describe an ele...

CLEP ChemistryJohn Dalton - correct answer Proposed that matter is composed of atoms; these atoms have different identities called elements, which combine to form compounds; measured masses of reactants and products. J.J. Thompson - correct answer Observed deflection of particles in a cathode ray tube; proposed that atoms are composed of positive and negative charges; developed the plum pudding model of the atom Robert Millikan - correct answer Calculated the charge-to-mass ratio of electr...

CLEP Chemistry Review Practice Questions 2024. John Dalton - correct answer Proposed that matter is composed of atoms; these atoms have different identities called elements, which combine to form compounds; measured masses of reactants and products. J.J. Thompson - correct answer Observed deflection of particles in a cathode ray tube; proposed that atoms are composed of positive and negative charges; developed the plum pudding model of the atom Robert Millikan - correct answer Calculated ...

GCSE EDEXCEL TRIPLE SCIENCE CHEMISTRY PAPER 2 2024/2025 QUESTION PAPER ALREADY PASSED What does 'aq' mean? - answer Aqueous - it is dissolved in water Water - formula - answer H20 Ammonia - formula - answer NH3 Carbon Dioxide - formula - answer CO2 Hydrogen - formula - answer H2 Chlorine - formula - answer Cl2 Oxygen - formula - answer O2 Ammonium (ion) - formula - answer NH4 (+) Hydroxide (ion) - formula - answer OH (-) Nitrate (ion) - formula - answer NO3 (-) Carbonate (ion) -...

AQA GCSE Chemistry - Paper 1 Exam Questions With Complete Solutions What is the charge of a proton? - ANSWER +1 What is the charge of a neutron? - ANSWER 0 What is the charge of an electron? - ANSWER -1 What is the relative mass of a proton? - ANSWER 1 What is the relative mass of a neutron? - ANSWER 1 What is the relative mass of an electron? - ANSWER Very small How many types of atoms do elements contain? - ANSWER Only one type What are compo...

Plasma - ANSWER ionized gas that has some electrons that are described as free because they are not bound to an atom or molecule specific gravity - ANSWER measurement of the density of substances in a liquid compared to water atomic theory - ANSWER a theory that states that all matter is composed of tiny particles called atoms. John Dalton - ANSWER developed modern atomic theory negative ion - ANSWER anion, gains electrons positive ion - ANSWER cation; loses electrons ionic bon...

AQA GCSE Chemistry Paper 1 2023 Exam Questions With Complete Solutions What is an atom? - ANSWER Smallest part of an element that can exist What is an element? - ANSWER A substance made up of one type of atom How are elements represented? - ANSWER Using symbols, in the periodic table Approximately how many elements are there? - ANSWER 100 What is a compound? - ANSWER A substance made up of two or more elements chemically c...

1. The term “atom” was first used by the _____. a. Ethiopians b. British c. Greeks d. Romans ANS: C The term “atom” was first used by the Greeks DIF: Moderate REF: page 27 OBJ: Relate the history of the term “atom.” 2. The first person to describe an element as being composed of identical atoms was _____. a. J. J. Thomson b. John Dalton c. Dmitri Mendeleev d. Niels Bohr ANS: B The first person to describe an element as being composed of identical atoms was John Dalton....

AC HPAT Chemistry Questions All Correct Answers single displacement - ANSWER- A + BC --> AC + B double displacement - ANSWER- AB + CD --> AD + CB precipitate - ANSWER- A solid that forms from a solution during a chemical reaction. energy level - ANSWER- Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. What is the atomic number of an element - ANSWER- number of protons What is the mass number of an el...