Which of the following is the correct chemical formula for Na and S?

Na2S

NaS2

NaS

If element x has 20 protons, how many electrons does it have

Consider the hydrate FeSO4 • 7H2O. What is the percent by mass of water in the hydrate? % What is the percent by mass of the anhydrous salt in the hydrate? %

Objects in free-fall ___. do not experience air resistance do not experience gravity are accelerating faster than 9.8 m/s/s are completely weightless

Seafloor spreading provides evidence of which of the following Earth processes? A. erosion of coastlines B. weathering of mountains C. movement of crustal plates D. formation of sedimentary rocks

Based on the law of conversation of mass, how does the mass of reactants compare with the mass of products in a given reaction?

What is the general term for a compound not containing the element carbon?

determine the specific heat of a material if a 35g sample absorbed 96 J as it was heated from 293 K to 313 K?

A compound that changes color when it comes into contact with an acid or base is an?

1. A food sample is burned in a calorimeter that contains 2000. g of water. The temperature increases from 22.0°C to 44.3 °C. How many Calories does the food sample contain, assuming all of the energy from the food was transferred into the water?

Why doesn't water light on fire? It has all the ingredients except heat! Hydrogen for the flammability factor, oxygen so it can keep burning, and all you need to do is add heat and BOOM you have a flame! 15 pts