know not everyone is a science geek like me, but I've gotta tell you, there's some pretty cool stuff that goes on in the kitchen when you're cooking. If you think about it, cooking is chemistry: You mix a few solids and liquids together, add heat, and voila! The flavor, color, texture, and odor of the foods all change (for better or worse). Whether you're the master of your kitchen or your kitchen masters you, allow me to unveil some kitchen chemistry mysteries for you.

Baking Mysteries
What's the difference between baking soda and baking powder? They're both leavening agents, which means they make batters rise when they are heated by creating tiny pockets of air. Baking soda is the agent used when a recipe contains enough acid (like orange juice or sugar) for the soda to react with. The reaction creates carbon dioxide gas, which helps form the air spaces. Baking powder is an acid agent mixed with baking soda that forms carbon dioxide when it comes into contact with the liquid in the batter. It is best used for recipes that contain little to no acid ingredients. Some recipes call for both because they may have too much acid and require baking powder to buffer the reaction to prevent the air bubbles from getting too big or exploding. A good rule of thumb is to use 1-1¼ teaspoon baking powder or ¼ teaspoon baking soda for every cup of flour you use.

Why do cookbooks recommend that I roll my pastry dough out on a marble surface? Intuitively, it seems like the answer is that marble is colder than wood or plastic, but if your kitchen is the same temperature in all areas, there's no way that any surface could be cooler or warmer than another. What's special about marble is that it draws heat away from physical objects. In other words, it conducts heat better than wood or plastic. It feels cooler to the touch because it pulls heat from your hand when you touch it. The action of rolling pastry creates heat, which would melt the chunks of butter required to make flaky dough. Marble helps to quickly draw the heat out of the dough before it can melt the butter.

Protein Mysteries
Why should you let meat or chicken rest for a few minutes after cooking? When a piece of meat or chicken is heated, the juices tend to flow out of the muscle, especially around the surface of the food. If you let it rest, the juices will have a chance to migrate evenly back into the muscle, and you will have a juicier, more tender piece of meat.

Why are my scrambled eggs always tough and watery? Because you cooked them over too much heat. When you heat eggs, the protein strands start to uncurl and knit together, making the egg solid and curd-like. If you rush this process by cooking over high heat, the proteins will form a very tight knit and squeeze the water out, creating tough, watery eggs. Beat eggs well, and add a little water for volume. Cook over low heat, stirring and scraping constantly and remove from heat just before they look done. You'll have perfectly creamy, billowy eggs.

Water Mysteries
Why does almost every recipe advise us to add salt to the water we use for boiling pasta? The popular conception is that it makes the water temperature increase faster and therefore shortens cooking time. The truth is, salt raises the boiling point of the water by less than one degree Fahrenheit, which makes absolutely no difference in cooking time. Add salt for flavor, before, during, or after cooking, but for no other reason.

Should I use hot or cold tap water for boiling? Although it's true that hot water would boil faster and shorten cooking time, it may also be unhealthy. Many older buildings are outfitted with copper pipes with lead-containing solder. Hot water running through the pipes can leech out some of the lead and end up in your cooking pot. Over time, this practice can cause lead poisoning. So spend the extra time and start cold — it may extend your life.

Fat Mysteries
How can nonstick cooking spray have no fat if it's made from fat? An emulsifier, like lecithin, is added to the oil to break it up into teeny tiny droplets. When it's sprayed, the droplets spread out to coat the pan with a very thin layer of oil that helps cook and brown food without using too much fat. If you look closely at the nutrition facts label, you'll notice that a serving of fat-free spray is a 1/3 second spray. Hold the spray for longer, and the calories and fat will start to pile up.

Now that your kitchen is a little less of a mystery, it's time for you to get cooking!