Kevin's science class did an experiment using baking soda, vinegar, a red balloon, and a flask. First, they filled the flask with vinegar and poured baking soda into the deflated balloon. Then, they placed the balloon over the mouth of the flask, being careful not to let the baking soda fall into the vinegar. They observed that the balloon was still deflated. Next, the students held the balloon up and allowed the baking soda to fall into the flask and mix with the vinegar. The mixture began to bubble, and the balloon began to inflate. Kevin thinks that a new substance must have been formed when the baking soda mixed with the vinegar. To help support this idea, Kevin makes several observations about the flask, the balloon, and the substance inside the flask after the baking soda and vinegar were mixed. Which of these observations provides the best evidence that a new substance formed? A. The liquid in the flask is clear. B. The balloon is inflated. C. The balloon is red. D. There is liquid in the flask.

Which function is performed by earths atmosphere? a. ultraviolet rays are prevented from reaching the ozone layer. b. earths temperature is raised and moderated by trapping in heat c. charged particles from the sun are prevented from reaching earth. d. magnetic charges from space are prevented from reaching earths surface.

Is a measure of the resistance to flow. a high liquid has a high resistance to flow and flows slowly. the ancients thought everything in the world was made of 4 we now know that there are 94 naturally occurring and scientists have created another 24 i am certain they will create even more. honey flows slowly because it has a high to flowing. a can be separated by physical means because it contains more than one pure substance and 2 pure substances are not chemically bonded to each other. a cannot be separated by physical means. all matter is made up of all elements are with the same number of protons. if it is just a single or many bonded together, if all of them have the same number of protons, it is an element. in a piece of pure iron metal, all the are joined together, that piece of iron metal is called elemental iron. a single of iron is called elemental iron. a mixture has differences from place to place. we might need a microscope to see them or they might be obvious to the unaided eye. there are surfaces separating it into different phases. a mixture is the same everywhere. it is uniform. there are no surfaces separating it into different phases. if different kinds of atoms (different elements) are bonded together by their electrons, it is called a there are physical means of to isolate the different pure substances in a mixture and there are chemical means of to isolate the different elements in a compound. 1. element 2. compound 3. mixture 4. heterogeneous 5. homogeneous 6. pure substance 7. atoms 8. separation 9. viscosity 10. resistance

Fred is studying a substance that is made out of only one element. this means that