MLT 118 Exam 1

the limit of chemical subdivision for matter (ex. NaCI)

Atoms

After heating, a pure substance, A, is found to produce both B and C. What can be said about the substance A?

It is a compound

It is an ion

It is an element

It is a atom

It is a compound

a chemical bond formed when the outermost electrons of one atom are permanently transferred to another atom

Ionic bond

two nonmetal atoms share electrons (ex. CO2)

Covalent bond

attracts an electronegative atom electrostatically (ex. H2O)

hydrogen bond

positive metal attract conducting electrons (ex. iron, copper — pure metals)

Metallic bond

________________are forces that hold the atoms together in a molecule.

Chemical bond

the limit of physical subdivision of a pure substance

molecule

pure substance made up of homoatomic molecules or individual atoms of the same kind (ex. oxygen, copper)

Element

pure substances made of of heteratomic molecules or individual atoms of two or more different elements (ex. water, h2O)

compound

composition is the same throughout (ex. soda)

Homogeneous (mixture)

Heterogeneous (mixture)

homogeneous (mixture)

composition is not the uniform (ex. oil in water, blood)

Heterogeneous (mixture)

loses and electron; is a positive charge

anions or cations?

Cations

gains a electron; has a negative charge

Anions or cations?

anions

Urea (CH₄N₂O) is an end-product of protein metabolism. Measurement of urea is one of the Renal Function Test (RFT) performed in clinical chemistry department. Calculate the molecular weight of urea. (Atomic mass of C= 12; N=14; O=16)

60 grams/mol

the study of structure, properties, composition, reactions and preparation of carbon-containing compounds

Organic chemistry

the study of properties of inorganic compounds (metals, minerals and organic-metallic compounds))

inorganic chemistry

This image shows the structural formula of an inorganic compound. True or False?

True

the study of chemical processes related to living organisms (lab based science/biology n chemistry)

biochemistry

What is “clinical chemistry”?

science focused on chemical analysis of body fluids such as blood urine, spinal fluids etc

Table salt dissolving in water is what kind of change?

physical change

Baking soda reacts to vinegar is what kind of change?

chemical change

What is required for a heterogeneous mixture (medicine) to be effective?

to be shaken; because the composition isn’t uniform (ex. oil n water for baking brownies)

A element that is a key indicator of organic substances. (It is present in the human body.)

carbon (C)

What kind of change is this:

chemical change

Which of the following is a physical property of matter?

a. produces a gas when placed in an acid

b. does not burn

c. a substance freezes at −70°C

d. the surface turns black in air

a substance freezes at −70°C

Table Salt (NACI) dissolves in water is what kind of change?

Physical change

An antacid seltzer tablet dissolved in water, correctly classified as:

Chemical change

In order for matter to change from a liquid to a gas, which of the following is true?

A) Energy must be removed from the liquid

B) The chemical composition of the gas must be altered

C) Energy must be applied to the liquid

D) The chemical composition of the liquid must be altered

C) Energy must be applied to the liquid

Which one of the following is not element in the human body?

A) Carbon

B) Oxygen

C) Plutonium

D) Hydrogen

E) Nitrogen

C) Plutonium

The chemical formula for methane is CH4. How many atoms are in a compound of methane?

A) 4

B) 3

C) 5

D) 6

C) 5

The atomic mass of Carbon is 12, and the atomic mass of oxygen is 16. What is the molecular weight of ONE molecule of carbon dioxide (CO2)?

A) 24

B) 28

C) 32

D) 44

D) 44 Exp.) 12(1)+16(2)

A particular laboratory reagent is a heterogeneous mixture. Since heterogeneous mixtures are consistent throughout, this reagent does not need to be shaken.

A) True B) False

B) False

(heterogeneous mixture Consist of two or more substances, needs to be mixed)

Which of the following is an example of a homogeneous mixture?

A) Table salt

B) Physiological saline

C) Opened soda

D) Oil & water suspension

B) Physiological saline

Air is a mixture of several gases, so it is a

heterogeneous mixture.

A) True

B) False

B) False

Blood is a heterogeneous mixture including red blood cells, white blood cells, platelets and plasma.

A) True

B) False

A) True

Which statement is true of micropipettes?

Some have preset volumes.

all of the above

A one-use disposable plastic tip is used for each sampling.

Some are adjustable in a narrow range.

all of the above

all of the above

The melting of frozen urine to liquid urine is correctly classified as:

a chemical change.

a physical change.

both a chemical and a physical change.

neither a chemical nor physical change.

a physical change.