If you have a mixture of water with activated carbon and common salt. Sequence Correct operations, to separate activated carbon and salt from this mixture, is: A) Filtration and decantation B) Evaporation and filtration C) Distillation and filtration D) Filtration and evaporation

How many grams of oxygen (O) are present in a 6.41 g sample of potassium nitrate (KNO3)? Enter your answer in decimal form with the correct number of sig figs. Use the proper abbreviation for the units. NOTE:  If you have taken chemistry before and know what diatomic means, do not take that into consideration.  Use just O for this.  There are reasons for this.

Assume the observable Universe is charge neutral, and that it contains n nuclei (hydrogen plus helium nuclei, ignoring other elements).  Take the helium mass fraction as 1/4.  How many electrons are there in the observable Universe?  Enter your answer in scientific notation with one decimal place.   n = 7*10^80

Potassium nitrate was synthesized in an experiment using 10 mL of nitric acid and excess potassium hydroxide. The mass data obtained from the experiment is shown in Table 1 below. Given that the percentage yield of potassium nitrate was 88.3 %, calculate the concentration (% m/v) of the nitric acid used in the experiment. Table 1: Mass data for the synthesis of potassium nitrate from nitric acid and potassium hydroxide Mass of clock glass and crystallized potassium nitrate/ g 45.55 Mass of empty clock glass/ g 39.18

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Explain your rationale for using the summative assessment (below) from the lesson plan on mixing substances in a 5th-grade classroom based on the below standard and learning objective, including how you will use student outcomes to inform future instructional decisions.  Summative Assessment  Summative: Components of the Lab Report Purpose: The student should clearly state the purpose of the experiment, which is to determine whether the mixing of two or more substances results in new substances. Procedure: The student should describe the steps they took to conduct the experiment. This includes the substances they chose to mix and the safety equipment they used. Observations: The student should record any observable changes that occurred when the substances were mixed. This could include a color change, the formation of a precipitate, or a change in temperature. Conclusion: The student should state whether a new substance was formed based on their observations. They should also…

g shape, color, Choose all that apply. A. The property can be observed without changing the identity of the substanca B. The property depends on the amount of the substance present. C. The state of the substance changes when you measure the property. D. The property can be observed or measured. EVIDENCE NOTEBOOK 19. How do the physical properties of the rocks at the beginning of the lesson differ? Are there physical properties that might differ, but that you cannot observe in the photos? Record your evidence. Lesson 1 The Properties