Pure helium gas is used in many industries in its liquid form as a refrigerant that allows for the liquefaction of many gases (including nitrogen and oxygen). It is also the gas of choice used when filling party balloons. Which of the following designations best describe pure helium gas [He(gl? It is an element. It is a compound. It is a homogeneous mixture. It is a heterogeneous mixture.

Q: Suppose a teaspoon of magnesium filling and a teaspoon of powdered sulfur are placed together in a…

A: MIXTURE : Mixture is defined as the physical combination of two or more different substances such…

Q: Classify each of the following as a physical change or a chemical change. For each chemical change,…

A: Physical change is the rearrangement of the molecules ( composition remains same) In Chemical change…

Q: Classify these substances. More than one answer may apply in each case. N2 solution O homogeneous…

A: Element - It is a pure substance made up of only a single atom.  Compound - It is a pure substance…

Q: Propane gas (C3H8), has a boiling point of -42.0oC and ignites in the presence of oxygen. Do these…

A:

Q: a substance has particles that are close together with no regular arrangement. the particles vibrate…

A: The objective of the question is to identify the state of matter of a substance based on its…

Q: Complete the following operation and determine the correct answer using the appropriate number of…

A: Numbers with decimals have some significant and some non significant figures.  All non zero digits…

Q: Which of the following is not a physical change? Frying an egg Boiling water Liquefying oxygen…

A: Physical change is the process where the apperance of the matter or the state of matter changes. But…

Q: Which of the following is a chemical property of tin? O It is easily malleable. It melts at 232°C.…

A:

Q: Classify these substances. More than one answer may apply in each case. H, pure substance element…

A:

Q: A glass of cold milk is an element, a compound, a homogeneous mixture or heterogeneous mixture?

A: A glass of cold milk is an element, a compound, a homogeneous mixture or heterogeneous mixture?…

Q: What is the difference between a chemical process and a physical process in chemistry

A:

Q: Two samples of solids have similar reactivity with acids and similar densities. Their masses and…

A: Extensive properties are the ones whose value depend on the size of the system like mass , volume…

Q: Which of the following represent a chemical change? Which of the following represents a physical…

A: We are to discuss which of gives changes are physical and chemical changes.

Q: 33.0 pl. drops of two different liquids are put on the same surface: Liquid X Liquid Y Note for…

A: Given that neither the liquid X nor the liquid Y interacts strongly with the surface. This means…

Q: Cite the evidence that indicates that only physical changes occur when a platinum wire is heated in…

A: Physical change means any kind of change of a substance's form like size, colour etc. without being…

Q: Which of the following is a mixture?  Brass, carbon monoxide, sulfur dioxide or salt

A: A mixture is formed due to the physical combination of substances bounded together in a…

Q: Explain the difference between a pure substance and a mixture?

A: A pure substance is composed of only one type of atoms or molecule.  Example: Distilled water

Q: Set the things below into the categories of either pure,mixture, heterogeneous mixture,element, pure…

A:

Q: Put a pinch of salt and sugar in a glass half filled with water. Stir the mixture to dissolve the…

A: When a mixture of salt, sugar and water is stirred, the salt and sugar (solutes) get dissolved in…

Q: Gaseous butane (CH, (CH,) CH,) will react with gaseous oxygen (0,) to produce gaseous carbon dioxide…

A:

Q: You strongly heat a tan-colored powdery solid directly on a hot plate in a vacuum chamber (so no air…

A: Since the unknown substance gives different colored substances, it is definitely not a pure element.

Q: Identify each of the following: (As: element, homogeneous mixture, heterogeneous mixture, compound,…

A: As per the regulations only first three subparts can be answered.   General properties of matter:

Q: A chemist mixes two liquids, A and B, to form a homogeneous mixture. The densities of the liquids…

A: The density of the metal object can be obtained by using the formula for the mixtures for densities…

Q: A group of students took turns using a laboratory balanceto weigh the water contained in a beaker.…

A: A group of students took turns using a laboratory balance to weigh the water contained in a beaker.…

States of Matter

The substance that constitutes everything in the universe is known as matter. Matter comprises atoms which in turn are composed of electrons, protons, and neutrons. Different atoms combine together to give rise to molecules that act as a foundation for all kinds of substances. There are five states of matter based on their energies of attraction, namely solid, liquid, gases, plasma, and BEC (Bose-Einstein condensates). 

Chemical Reactions and Equations

When a chemical species is transformed into another chemical species it is said to have undergone a chemical reaction. It consists of breaking existing bonds and forming new bonds by changing the position of electrons. These reactions are best explained using a chemical equation.