A. (cold solutions hold on to their solutes better)
Answer:
4Cr + 3O2 —> 2Cr2O3
Explanation:
Information from the question include:
Chromium + oxygen -> chromium(III) oxide
From the word equation given above, the equation can be written as follow:
Cr + O2 —> Cr2O3
The equation can be balance by doing the following:
There are 2 atoms of O on the left side and 3 atoms on the right side. It can be balance by putting 2 in front of Cr2O3 and 3 in front of O2 as shown below:
Cr + 3O2 —> 2Cr2O3
Now, we have 4 atoms of Cr on the right side and 1 atom on the left. It can be balance by putting 4 in front of Cr as shown below:
4Cr + 3O2 —> 2Cr2O3
Now the equation is balanced
Answer:
You can do that yourself, but there's a example question below. And, if for example, I just answer your question and you don't even try to answer. it dosent matter.
Explanation:Force=Mass x Acceleration -or- F=ma
where F is the force, m is the mass, and a is the acceleration. The units are Newtons (N) for force, kilograms (kg) for mass, and meters per second squared (m/s2) for acceleration. The other forms of the equation can be used to solve for mass or acceleration.
m=F/a and a=F/m Example:
Engineers at the Johnson Space Center must determine the net force needed for a rocket to achieve an acceleration of 70 m/s2. If the mass of the rocket is 45,000 kg, how much net force must the rocket develop?
Using Newton's second law, F=ma
F=(45,000 kg)(70 m/s2) = 3,150,000 kg m/s2 F=3,150,000 N Note that the units kg m/s2 and newtons are equivalent; that is, 1 kg m/s2
Answer: The density of the unknown metal is 7.86 g/ml.
Explanation:
Density is defined as the mass contained per unit volume.
Given : Mass of metal = 25.32 g
Volume of metal = volume of water displaced = (28.22 - 25.00) ml = 3.22 ml
Putting in the values we get:
Thus the density of the unknown metal is 7.86 g/ml
Answer:
K, the rate constant = 9.73 × 10^(-1)/s
Explanation:
r = K × [A]^x × [B]^y
r = Rate = 1.07 × 10^(-1)/s
K = Rate constant
A and B = Concentration in mol/dm^-3
A = 0.44M
B = 0.11M
x = Order of reaction with respect to A = 0
y = Order of reaction with respect to B = 1
Solving, we get
r/([A]^x × [B]^y) = K
K = 1.07 × 10^(-1)/s/(0.44^0 × 0.11^1)= 0.9727
K = 0.9727
