Answer:
Mixture.
Explanation:
Hello,
In this case, when blending we are continuously sliding the substances until we obtain small particles that when do not chemically but physically combine we say they are forming a mixture. Nevertheless, when they chemically combine they form a chemical compound due to the formation of bonds between them.
Regards.
Answer:
138 mg
Explanation:
A company is testing drinking water and wants to ensure that Ca content is below 155 ppm (= 155 mg/kg), that is, <em>155 milligrams of calcium per kilogram of drinking water</em>. We need to find the maximum amount of calcium in 890 g of drinking water.
Step 1: Convert the mass of drinking water to kilograms.
We will use the relation 1 kg = 1000 g.

Step 2: Calculate the maximum amount of calcium in 0.890 kg of drinking water

Answer:
51 J
Explanation:
The air inside a bicycle tire pump has 27 joules of heat conducted away. By convention, when heat is released, it takes the negative sign, so Q = -27 J.
77.9 joules of work done are being done on the air inside a bicycle tire pump. By convention, when work is being done on the system, it takes the positive sign, so W = 77.9 J
We can calculate the change in the internal energy (ΔU) using the following expression.
ΔU = Q + W
ΔU = (-27 J) + 77.9 J
ΔU = 51 J
This substance most likely is an inert. It is a substance that is not chemically reactive. It does not change its chemical nature in a reaction. It does not <span>easily react with other chemicals. Most of the group 8 gases in the periodic table are classified as inert, due to their having full outer electron shells. </span>