Questions posted in Chemistry

Mass is the actual amount of material contained in a body and is measured in kg, gm, etc. Whereas weight is the force exerted by the gravity on that object mg. Note that mass is independent of everything.

I think the answer is atoms

2H2 (g) + O2 (g) -->2H2 O(g)
mole ratio of H2:O2=2:1
7.25/2=3.625

According to Coulomb’s law, the ionic compound A–D has the smallest electrostatic potential energy is NaI.

because electrostatic potential depends on the charge whether it is positive or negative. since here, all of them F, Cl, Br and I have a negative charge. And the sizes of  F < Cl < Br < I are in this order. 

So they can tell if the researcher was lying/making up data.  Or to give constructive critisicm on how the test could be improved

The subatomic particles you describe are Electrons.

What is the units of k in the following expression: rate = k[A][B]?

A) s^-1
B)M^-1 s^-1
C)M^-2 s^-1
D)M

ans: B

Sand can be separated from a mixture of sand and water using filtration. That's because sand does not dissolve in water.

The melting of the ice cube indicates physical change has taken place

At first, the temperature of liquid nitrogen ensures that the air in the balloon doesn't take much volume. The temperature being optimal for liquid nitrogen makes sure that the nitrogen stays liquid, however, as the temperature increase and the balloon begins to heat up the nitrogen in the balloon begins to boil due to its boiling point being very low and the volume beings to increase. This causes the balloon to grow in size. Using Charle's law it can be determined that the volume of a gas in any space is proportional to the absolute temperature of such gas.

The molecular weight (g/mole) grams =moles * g/mole

The answer would be H++OH- -> H20 (Third option on the edgenuity assignment)

The system will then shift to the left, making more reactants.

I believe this force would be called pressure!

I believe from what I have read is there either one or five! I'm not too sure but I think that's correct!

33%, according to Quizlet

So, a basic principle of the Universe is that particles WILL ALWAYS ENTER THE STATE OF LOWEST ENERGY. Because there are already so many electrons in the 3rd energy level, it jumps to the 4s level because there is less energy in the 4s level (because even though it's further out, there aren't that many electrons repelling it) — so it jumps to the place with lowest energy.

C-Chlorine
H-Hydrogen
E-Einsteinium
M-Magnesium
I-Iodine
S-Sulfur
T-Tantalum
R-Radon
Y-Yttrium 

To find out the answer, we must know the mass percentage of Cu in the mineral chalcopyrite.

Mass percentage of Cu = molar mass of Cu/molar mass of chalcopyrite = 64/(64+56+32*2) = 34.8%.

So to obtain 210 g pure Cu, the amount of mineral need = mass of Cu/mass percentage of Cu = 210 g/34.8% = 603 g = 0.603 kg.

Checking the dining area of an eating establishment for evidence of flaking paint, broken light bulbs and wood damage will reduce the chances of PHYSICAL CONTAMINATION OF FOOD. Many food safety guidelines had been produced by the Food and Drug Administration to ensure public food safety in restaurants and other public eateries. 

All except for C. And it's good for the environment.

What kind of geometry does the following molecule have? CF4 - Tetrahedral

What causes water molecules to have the shape they have, according to VSEPR theory? C. repulsive forces between specific electrons

Your answer would be b

The correct answer would be the first option. The arrows 1, 2 and 3 represent the phase transitions where heat energy is gained. As heat energy is gained the kinetic energy of the molecules in a substance is increased which would cause them to change phases from solid to liquid and to gas.

That would be 100 degrees C or 212 F

The darn answer u nimbisol is the opposite

Density equals mass over volume. Density = 8.0 divided by 25 
hope i helped(:

In which region is the substance in both the solid phase and the liquid phase ?
2

Answer:  Region 3

Explanation:  The temperature and time graph suggests that region 3 is the region in which the substance can co exist in both the phases that is solid phase and liquid phase.

Region 1 explains that the the solid has just started melting and there occurs a break point and then region 2 again explains that the solid is taking more time with temperature to get converted into the liquid and thus region 3 explains the equilibrium between the two phases.