Q1Trace elements are those required by an organism in only minute quantities. Which of the following is a trace element that is required by humans and other vertebrates?
a.nitrogen
b. calcium
c. iodine
d. sodium
e. phosphorus
Q2 Which of the following statements is FALSE
a.Atoms of the various elements differ in their number of subatomic particles
b. all atoms of a particular element have the same number of protons in their nuclei
c. the neutrons and protons present in the nucleus of an atom are almost identical in mass;each has a mass of about 1 dalton
d. an atom is the smallest unit of an element that still retains the properties of the element
e. protons and electrons are electrically charges particles. Protons have one unit of negative charge, and electrons have one unit of positive charge.
Q3 each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atoms nucleus?
a.atomic mass
b.atomic weight
c. atomic number
d. mass weight
e. mass number
a.nitrogen
b. calcium
c. iodine
d. sodium
e. phosphorus
Q2 Which of the following statements is FALSE
a.Atoms of the various elements differ in their number of subatomic particles
b. all atoms of a particular element have the same number of protons in their nuclei
c. the neutrons and protons present in the nucleus of an atom are almost identical in mass;each has a mass of about 1 dalton
d. an atom is the smallest unit of an element that still retains the properties of the element
e. protons and electrons are electrically charges particles. Protons have one unit of negative charge, and electrons have one unit of positive charge.
Q3 each element is unique and different from other elements because of the number of protons in the nuclei of its atoms. Which of the following indicates the number of protons in an atoms nucleus?
a.atomic mass
b.atomic weight
c. atomic number
d. mass weight
e. mass number