Chm 130 Midterm Exam Questions With 100% Guaranteed Answers

Chemistry - correct answers The study of the composition, structure, properties, and reactions of matter Scientific Method - correct answers The process of making observations, proposing a hypothesis, testing the hypothesis, and developing a theory that explains a natural event 1. Observation 2. Hypothesis 3. Experimenet 4. Conclusion or theory - correct answers What are the four steps of the scientific method? Chemical - correct answers A substance that has the same composition and properties wherever it is found Experiment - correct answers A procedure that tests the validity of a hypothesis; control group, experiment group, and variables are used Hypothesis - correct answers An unverified explanation of a natural phenomenon Observation - correct answers Information determined by noting and recording a natural phenomenon Theory - correct answers An explanation of an observation that has been validated by repeated experiments that support a hypothesis Conversion Factor - correct answers A ratio in which the numerator and denominator are quantities from an equality or given relationship Density - correct answers The relationship of the mass of an object to its volume, expressed as g/cm3, g/mL, gL What is the equation for density? - correct answers d = m/V Equality - correct answers A relationship between two units that measure the same quantity Exact number - correct answers A number obtained by counting or definition Mass - correct answers A measure of the quantity of material in an object Measured number - correct answers A number obtained when a quantity is determined by using a measuring device Metric System - correct answers A system of measurement used by scientists and in most countries of the world Prefix - correct answers The part of the name of a metric unit that precedes the base unit and specifies the size of the measurements; all prefixes are related on a decimal scale Scientific notation - correct answers A form of writing larger and small numbers using a coefficient that is greater than 1 but less than 10, followed by a power of 10 meter (m) - correct answers What is the metric unit of length? 1 m = 1.094 yd 1 m = 39.37 in. 1 m = 100 cm 2.54 cm = 1 in. - correct answers What are some common conversions of length? liter (L) - correct answers What is the metric unit of volume? 1 m3 = 1000 L 1 L = 1000 mL 1 mL = 1m3 1 L = 1.057 qt 946.3 mL = 1 qt - correct answers What are some common conversions of volume? gram (g) - correct answers What is the metric unit of mass? 1 kg = 1000 g 1 kg = 2.205 lb 453.6 g = 1 lb - correct answers What are some common conversions of mass? degree Celsius (*C) - correct answers What is the metric unit of temperature? second (s) - correct answers What is the metric unit of time? 1 day = 24 h 1 h = 60 min 1 min = 60 s - correct answers What are some common conversions of time? 1. All non-zero digits are significant 2. Any zero in between significant figures is significant 3. Any zero that is after the decimal place and has a significant figure somewhere in front of it, is significant 4. Any zero at the end of a non-decimal number is not significant - correct answers What are the rules of significant figures? tera -T- trillion giga -G- billion mega -M- million kilo -K- thousand - correct answers What are some prefixes that increase the size of a unit? deci -d- tenth centi -c- hundredth milli -m- thousandth micro millionth nano -n- billionth pico -p- trillionth fento -f- quadrillionth - correct answers What are some prefixes that decrease the size of a unit? Calorie (cal) - correct answers The amount of heat energy that raises the temperature of exactly 1 g of water by exactly 1*C; 1 cal = 4.184 J Chemical change - correct answers A change during which the original substance is converted into a new substance that has a different composition and new chemical an physical properties; burning wood or lighting a firework Chemical properties - correct answers The properties that indicate the ability of a substance to change into a new substance; combustibility, flammability Compound - correct answers A pure substance consisting of two or more elements, with a define composition, that can be broken down into simpler substances only by chemical methods Element - correct answers A pure substance containing only one type of matter, which cannot be broken down by chemical methods; anything directly off the periodic table Energy - correct answers The ability to do work Gas - correct answers The state of matter that does not have a definite shape or volume Heat - correct answers Energy that flows from a hotter object to a cooler one Heterogeneous mixture - correct answers A mixture of two or more substances that are not mixed uniformly Homogeneous mixture - correct answers A mixture of two or more substances that are mixed uniformly Joule (J) - correct answers The SI unit of heat energy; 4.184 J = 1 cal Kinetic energy - correct answers A type of energy that is required for actively doing work; energy of motion Liquid - correct answers A state of matter that takes the shape of the container but has a definite volume Matter - correct answers The material that makes up a substance and has mass and occupies space Mixture - correct answers The physical combination of two or more substances that does not change the identities of the mixed substances Physical change - correct answers A change in which the physical properties of a substance change without any change in its identity; boing water or tearing a piece of paper