I believe the answer is an explosion
Answer: Fe<em>(aq)</em>+S<em>(aq)</em>=FeS<em>(s)</em>
Explanation: The Sodium and Bromine are spectator ions because they don't react with anything, you can see this by writing the ionic equation like so:
1.) Molecular formula (given): FeBr2 (aq)+Na2S (aq)= FeS(s)+2NaBr(aq)
Each dissolved FeBr2 breaks up into one Fe with a charge of 2+ and two Br with a negative charge. This gives you:
Fe(aq)+ 2Br(aq)+Na2S(aq)=FeS(s)+2NaBr
2.) Now repeat what was shown with the other compounds in the given molecular formula, and pay attention to the states that each ion is in (solid, liquid, aqueous, gas) because this will give you the ionic equation, which from there you can get rid of any ions that don't change amount or state.
3.) Ionic formula: Fe(aq)+ <u>2Br(aq)</u>+<u>2 Na(aq)</u>+S (aq)=FeS(s)+<u>2 Na(aq)+2Br(aq)</u>
4.)When you've derived a total ionic equation (above), you'll find that some ions appear on both sides of the equation in equal numbers. For example, in this case two Na cations and two Br anions appear on both sides of the total ionic equation. What does this mean? It means these ions don't participate in the chemical reaction. They're present before and after the reaction. Nothing happens to them. So those are removed and you're left with the net ionic: Fe(aq)+S(aq)=FeS(s)
Hope this helps :)
Answer: 
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)

Putting in the values:

![5.29=-log[H^+]](https://tex.z-dn.net/?f=5.29%3D-log%5BH%5E%2B%5D)
![[H^+]=5.1\times 10^{-6}](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3D5.1%5Ctimes%2010%5E%7B-6%7D)
Thus
is 
Answer:
Work done = 600 J
Power used = 60 W
Explanation:
Given:
Force acting on the box is, 
Displacement of the box is, 
Time taken for the work, 
Now, we know that, work is said to be done by a force only when there is displacement caused by the force in its direction.
Here, the force acting on the box causes a displacement of 30 m in its direction. So, work done is equal to the product of force and displacement caused.
Therefore, work done on the box is given as:

Therefore, the work done is 600 J.
Now, we know that, power is given as work done per unit time.
So, power used is given as:

Therefore, the power used is 60 W.
Mass is measured against a standard by using a balance. The statement given above is a fact. Therefore the answer among the choices is letter "A" or "A. True". I hope this helps you on your assignment.