Answer:
A mixture of molecules is a group of molecules in which there are multiple different elements and atoms, that are in either fixed proportions or random. There are heterogeneous and homogenous mixtures.
Explanation:
When an ionic is placed in water a dissolving reaction occurs so the positive or negative ion are only attracted to each other
Answer: <em>When you take the top off of a bottle of soda, the pressure inside the bottle decreases and goes to the same pressure as the atmosphere. When that happens the carbon dioxide inside is no longer forced to be a liquid and turns back into a gas, causing the bubbles that we're so familiar with.</em>
Explanation:
However, producing foaming carbon dioxide gas by shaking a bottle of soda water is a physical change, while producing foaming carbon dioxide gas by combining baking soda and vinegar is a chemical change. ... Because no chemical bonds are broken and no new molecules are formed, this is a physical change in the system.
Problem One
You will use both m * c * deltaT and H = m * heat of fusion.
Givens
m = 12.4 grams
c = 0.1291
t1 = 26oC
t2 = 1204
heat of fusion (H_f) = 63.5 J/grams.
Equation
H = m * c * deltaT + m * H_f
Solution
H = 12.4 * 0.1291 * (1063 - 26) + 12.4 * 63.5
H = 1660.1 + 787.4
H = 2447.5 or 2447.47 is the exact answer. I have to leave the rounding to you. I have no idea where to round it although I suspect 2450 would be right for 3 sig digs.
Problem Two
Formula and Givens
t1 = 14.5
t2 = 50.0
E = 5680
c = 4.186
m = ??
E = m c * deltaT
Solution
5680 = m * 4.186 * (50 - 14.5)
5680 = m * 4.186 * (35.5)
5680 = m * 148.603 * m
m = 5680 / 148.603
m = 38.22 grams That isn't very much. Be very sure you are working in joules. You'd leave that many grams in the kettle after drying it thoroughly.
m = 38.2 to 3 sig digs.
The first step in the scientific methods is ask a question
