Chemical reaction: Pb(NO₃)₂(aq) + 2KI(aq) → PbI₂(s) + 2KNO₃(aq).
aq(<span>aqueous)
means dissolved in water.
s(solid) means that salt (in this reaction </span>PbI₂) not dissolved in water.
This chemical reaction is double displacement reaction - cations (Pb²⁺ and K⁺) and anions (NO₃⁻ and I⁻) <span>of the two reactants switch places and form two new compounds.</span>
A penny is made of a silver core with a copper coating. Although you can not see the sliver underneath, it is therefore, a homogenous mixture. It is an evenly distributed mixture of copper Cu, and Silver Ag.
Answer: the correct answer is "land breeze"
Explanation:
<span>1.6 g
First, calculate the change in temperature.
30.5 - 23.2 = 7.3 K
Now we have 3 pieces of data, the units involved are K, J/(g K), and J. We wish to create a result with the units being g. Let's start with the specific heat.
0.90 J/(g K)
Now let's cancel out the K by multiplying by our data with K
0.90 J/(g K) * 7.3 K = 6.57 J/g
Now we want to cancel out the J and get g on top. We can do that by dividing the J value we have by the calculated value above. So
10.3 J / 6.57 J/g = 1.567732116 g
Rounding to 2 significant figures gives us a mass of 1.6 g
Remember, for most problems, simply look at the units you have and what you desire for the units in the final result. By paying attention to this, the math operations you need are pretty automatic.</span>
1. Kinetic energy
2. Potential energy
