What are the four observations that confirm that a chemical reaction is happening?

2. The combustion of heptane (C7H16) in oxygen spontaneously occurs. The products of the reaction are carbon dioxide and water vapor. The enthalpy of this reaction is - 2877.5 kJ.

What do the symbols tell you about the conditions of the reaction shown to the right? Check all of the boxes that apply. - The reaction only goes toward the products. - The reactant is dissolved in water. - A gas and a liquid are produced.

A resting object exerts pressure equals to

Is it possible to decrease resistance of the wire without changing the material it's made out of?

Balance the following Equation: ___Zn + ___HCl - -> ___ZnCl2 + ___H2 50g of zinc are reacted with 50g of hydrogen chloride. Calculate the amount of excess reactant. A - 4.2g B - 5.1g C - 1.4g D - 2.3g

Which of the following is an example of an electric force that occurs in atoms

5. What is another name for Newton's first law in your own words.

The molar mass of magnesium (Mg) is 24.30 g/mol. There are 6.02 1023 atoms in 1 mol. How many atoms are present in 48.60 g of Mg? 3.32 10^-24 atoms 1.96 10^-21 atoms 1.20 10^24 atoms 7.11 10^26 atoms

Add 3.76 * 104 and 5.5 * 102 and write the answer in scientific notation. A. 9.26 * 104 B. 9.26 * 106 C. 3.82 * 106 D. 3.82 * 104

In a dynamic equilibrium between the liquid state and the gas state, what is true about the rate of evaporation? a. greater than rate of condensation b. less than rate of condensation c. equal to rate of condensation d. cannot be determined.