Q: Answer the following question given this paragraph: Chemistry is based on the modern atomic theory, which states that all matter is composed of atoms. Q: What branch of science is based on the modern atomic theory, which states that all matter is composed of atoms? A: | OPTIONS:
- physics
- psychology
- biology
- chemistry
A: chemistry

Q: Answer the following question given this paragraph: Summary Superconductors are solids that at low temperatures exhibit zero resistance to the flow of electrical current, a phenomenon known as superconductivity. The temperature at which the electrical resistance of a substance drops to zero is itssuperconducting transition temperature (Tc). Superconductors also expel a magnetic field from their interior, a phenomenon known as the Meissner effect. Superconductivity can be explained by the BCS theory, which says that electrons are able to travel through a solid with no resistance because they couple to form pairs of electrons (Cooper pairs). Hightemperature superconductors haveTc values greater than 30 K. Q: Superconductors expel a magnetic field from their interior. what is this phenomenon known as? A: | OPTIONS:
- weissenberg effect
- eibner effect
- lauer effect
- meissner effect
A: meissner effect

Q: Answer the following question given this paragraph: Beta decay occurs when an unstable nucleus emits a beta particle and energy. A beta particle is an electron. It has a charge of -1. In nuclear equations, a beta particle is represented by the symbol . The subscript -1 represents the particle's charge, and the superscript 0 shows that the particle has virtually no mass. Nuclei contain only protons and neutrons, so how can a nucleus emit an electron? A neutron first breaks down into a proton and an electron (see Figure below ). Then the electron is emitted from the nucleus, while the proton stays inside the nucleus. The proton increases the atomic number by one, thus changing one element into another. Q: What occurs when an unstable nucleus emits a beta particle and energy? A: | OPTIONS:
- nucleus decay
- alpha decay
- methane decay
- beta decay
A: beta decay

Q: Answer the following question given this paragraph: The following ideas are important in understanding hybridization: 1. Hybrid orbitals do not exist in isolated atoms. They are formed only in covalently bonded atoms. Hybrid orbitals have shapes and orientations that are very different from those of the atomic orbitals in isolated. Q: Hybrid orbitals are formed only in which type of bonded atoms? A: | OPTIONS:
- ionically
- partially
- thermally
- covalently
A: covalently