Density is also an important physical property of matter. The concept of density combines what we know about an objects mass and volume. Density reflects how closely packed the particles of matter are. When particles are packed together more tightly, matter is more dense. Differences in density of matter explain many phenomena. It explains why helium balloons rise. It explains why currents such as the Gulf Stream flow through the oceans. It explains why some things float in or sink. You can see this in action by pouring vegetable oil into water. You can see a colorful demonstration in this video.

Question: "What is density?"

Response: "How closely packed the particles of matter are"

A: yes

Ratners Group PLC, a fast-growing, acquisition-minded London-based jeweler, raised its price for Seattle-based specialty jeweler Weisfield's Inc. to $57.50 a share, or $62.1 million, from $50 a share, or $55 million, after another concern said it would be prepared to outbid Ratners's initial offer. The other concern wasn't identified. Ratners's chairman, Gerald Ratner, said the deal remains of "substantial benefit to Ratners." In London at mid-afternoon yesterday, Ratners's shares were up 2 pence (1.26 cents), at 260 pence ($1.64). The sweetened offer has acceptances from more than 50% of Weisfield's shareholders, and it is scheduled for completion by Dec. 10. The acquisition of 87-store Weisfield's raises Ratners's U.S. presence to 450 stores. About 30% of Ratners's profit already is derived from the U.S.

Question: "How many of Weisfield's stores are to be liquidated and acquired by Ratners by Dec. 10?"

Response: "450"

A: no

If you build a campfire, you start with a large stack of sticks and logs. As the fire burns, the stack slowly shrinks. By the end of the evening, all that is left is a small pile of ashes. What happened to the matter that you started with? Was it destroyed by the flames? It may seem that way. What do you think happened? The truth is that the same amount of matter still exists. The wood changed not only to ashes, but also to carbon dioxide, water vapor, and other gases. The gases floated off into the air, leaving behind just the ashes. Although matter was changed, it was not created or destroyed. Because the same amount of matter still exists, we can say that matter is conserved. You may wonder how it can be conserved if something is now missing? Assume you had measured the mass of the wood before you burned it. Assume you had also trapped the gases released by the burning wood and measured their mass and the mass of the ashes. What would you find? The ashes and gases combined have the same mass as the wood you started with. This example illustrates the law of conservation of mass.

Question: "After you burn wood in your campfire, the wood matter ends up on the ground (mostly as ashes), but where does the rest of the matter go?"

Response: "It is destroyed in the air"

A:
no