Which of the following contribute(s) to most of the mass of an atom? Question 6 options:

A)

Neutrons only

B)

Protons and neutrons

C)

Protons and electrons

D)

Protons only
Question 7 (5 points)
In a certain chemical reaction, the bonds of the products contain more energy than the bonds of the reactants. For the reaction to occur, which of the following best describes what occurred?
Question 7 options:

A)

Energy was released, so the reaction is endothermic.

B)

Energy was released, so the reaction is exothermic.

C)

Energy was added, so the reaction is endothermic.

D)

Energy was added, so the reaction is exothermic
Question 8 (5 points)
A solution
Question 8 options:

A)

is a single-phase homogeneous mixture.

B)

must contain water.

C)

is always a liquid.

D)

can contain more than two phases.
Question 9 (5 points)
Which of the following is true of alloys?
Question 9 options:

A)

They can only be composed of metals.

B)

They must be held together by chemical bonds.

C)

They're liquid solutions.

D)

They must contain a metal.
Question 10 (5 points)
Which of the following best describes an atomic number? An element's identity is defined by its atomic number; this means it represents the number of
Question 10 options:

A)

electrons in the element.

B)

neutrons in its nucleus.

C)

protons plus neutrons in its nucleus.

D)

protons in its nucleus.

What mass of carbon dioxide is produced from the complete combustion of 4.50×10−3 g of methane?

1. an experiment in your science class lists the materials needed for the lab. it is your job, as a lab partner, to measure out 25 ml of distilled water and 2.5 grams of magnesium. what lab measuring tools would you choose to measure each substance and how would you use each tool to get the correct amounts? be sure to describe the process you would follow step-by-step. (5 points) 2.which of the following is an si base unit for measuring mass? (2 points) ampere gram meter pound 3.which of the following is an si base unit for time? (2 points) decades hours minutes seconds 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer 4.which of the following tools should a scientist use to measure an object in milligrams? (2 points) graduated cylinder pan balance tape measure thermometer. 5.a pencil beside a metric ruler. the ruler is scaled from 1 centimeter to 10 centimeters, with markings for millimeters between each number. one end of the pencil is beside the 0 on the ruler, and the pencil point is beside the 5. which of the following measurements is accurate but not precise? (2 points) 5 mm 5 cm 50 mm 50 cm 6. which of the following prefixes represents the largest value? (2 points) giga hector kilo milli 7. which of the following types of graphs is best for plotting the percentages of a whole value in a data set? (2 points) bar graph circle graph histogram line graph

When utilizing a transmission electron microscope, why is it necessary to stain the specimen with heavy metal salts?