protons. ____ 6. Which of the following includes the others? a. protons b. neutrons c. electrons d. atoms ____ 7. What holds together the two strands of a DNA molecule? a. hydrogen bonds b. covalent bonds c. polar ionic bonds d. nonpolar ionic bonds ____ 8. The maximum number of electrons in the shell closest to the nucleus is a. four. b. eight. c. two. d. one. ____ 9. A molecule of liquid water a. is nonpolar. b. is locked in a rigid three-dimensional
Premium Atom DNA Covalent bond
Analytical chemistry Analytical chemistry is the branch of chemistry that deals with the separation‚ identification and determination of components in a sample. Analytical chemistry can be divided into two branches‚ qualitative and quantitative. Qualitative analysis It deals with the identity of the constituents that are in an analytical sample. Quantitative analysis It deals with the determination of how much of a given substance is in the sample. The quantitative analyses are classified
Free Atom
1. Question : Richard was observing black swallowtail butterflies in the field. Which one of these is an observation he made about a black swallowtail butterfly? The black swallowtail laid its eggs on a parsley plant. Question 2. Question : The most valid and reliable test of the hypothesis‚ more pine seeds germinate after a forest fire‚ would include an experimental group of pine seeds that was recovered from a fire area and pine seeds that were — tolerant of fire. Question 3
Premium Chemical bond Ionic bond Covalent bond
types of bonds to know: IONIC bonds: form betw. two atoms when electrons are transferred from one atom to the other. Occurs when the electronegativities of the two atoms are very different and one atom has a much stronger pull on the electrons than the other atom. One atom gains electrons and has an overall negative charge and the other atom loses electrons and has an overall positive charge – these atoms are ions and the attraction of their opposite charges constitutes the ionic bond. (EX: NaCl) COVALENT
Free Atom Electron Ion
Bonding Three types of bonds Ionic bond: 2 oppositely charged atoms (Na and Cl) Polar covalent: Unequally shared electrons (H and O) Non polar covalent: Equally shared electrons (C and C) or similar electronegativity Electronegativity and chemical bonding Electronegativity is a measure of the strength in which an atom can attract electrons. A difference of < 0. 5 is non polar covalent bond A difference of 0.5 – 1.7 is polar covalent bond A difference of > 1.7 is ionic bond Intermolecular forces
Free DNA Protein Enzyme
(reducing potential energy). The positive end of a polar molecule will attract the negative end of the other molecule and influence their arrangement. Dipole-dipole forces have strengths that range from 5 kJ to 20 kJ per mole. They are much weaker than ionic or covalent bonds and have a significant effect only when the molecules involved are close together (touching or almost touching). London Dispersion London dispersion forces are a type of force acting between atoms and molecules. It is caused by
Premium Atom Chemical bond Covalent bond
There are many similarities and differences between Greek and Roman temples. Through examining the Temple of Hera‚ the Parthenon‚ and Maison Carre‚ we are able to compare and contrast Greek and Roman temples. First‚ it is important to note what the specific characteristics for each type of temple usually are. In a Greek temple‚ there are stairs all the way around the architecture and free-standing columns all the way around as well. A good example of a Greek temple‚ is the Temple of Hera
Premium Ancient Rome Ancient Greece Roman Empire
These include ionic bonds‚ hydrogen bonds‚ van der Waal forces‚ and hydrophilic interactions. Each of these types of interactions are different by the way each of them interact with other molecules: Ionic bonds are attractions between charged atoms; hydrogen bonds are attractions between polar groups when a hydrogen is bounded to a high electronegativity-charged
Premium Atom Electron Chemical bond
CHEM161 Experiment 7: Calorimetry Introduction Calorimetry is the science of measuring heat flow‚ and heat is defined as thermal energy flowing from an object at a higher temperature to one at a lower temperature. For example‚ if a chunk of metal at room temperature is placed in a beaker of boiling water‚ the metal will absorb heat from the water until it is at the same temperature as the boiling water. Scientists also often study the heat associated with different physical and chemical changes
Premium Sodium hydroxide Chemical reaction Thermodynamics
types of solids are held together by strong dipole-dipole interactions. Example: Solid SO 2 ‚ solid NH3 Hydrogen-bonded molecular solids → The molecules of such solids contain polar covalent bonds between H and f‚ O or N atoms. Example: Ice (H2 O) Ionic solids Ions are the constituent particles; e.g.‚ NaCl‚ KNO 3 Metallic solids Each metal atom is surrounded by electrons; e.g.‚ Fe‚ Cu Covalent or network solids Formed by covalent bonds; e.g.‚ diamond‚ silicon carbide General characteristics of
Premium Crystal system Solid Crystal structure