Which of the following consists of a single element or type of compound?

Heterogeneous mixture

Homogeneous mixture

Impure substance

Pure substance

How many liters of nitrogen gas are needed to react with 90.0 g of potassium at STP in order to produce potassium nitride according to the following reactions?

Which of the following ionic compounds would have the most negative lattice energy: NaCl, KCl, or MgCl2? Explain your answer.

A student performs the following procedure: Procedure 1. Measure 25 grams of an unknown solid. 2. Measure 200 grams of water. 3. Pour the unknown solid and water into beaker, which weighs 50 grams. 4. Stir the solution.

Given the balanced equations representing two chemical reactions:Cl2 + 2NaBr - - - > 2NaCl + Br2 2NaCl---> 2Na + Cl2 Which types of chemical reactions are represented by these equations?

What country absorbs more co2 than it gives off?

Calculate the moles of new H₂ O₂ using the balanced formula below and the average moles of KMnO₄ from calculation #2. The average moles of KMnO₄ is 0.90mol. 2KMnO₄ + 5H₂O₂ + 3H₂SO₄ → K₂SO₄ + 2MnSO₄ + 8H₂O + 5O₂ Edit: I got 2.

How many grams of CaC2 would make 23.6g C2H2?

Shane performed the following trials in an experiment. Trial 1: Heat 30.0 grams of water at 0 °C to a final temperature of 40.0 °C. Trial 2: Heat 40.0 grams of water at 10.0 °C to a final temperature of 40.0 °C.

According to the law of conservation of ___ in an isolated system the initial total momentum before a collision equals the final total momentum.

What is the correct name fore this formula Al2O3