Answer:
Density=2kg/6m^3=1/3 kg/m^3
Explanation:
Answer:
Take for example I₂ (iodine)
Explanation:
It has only a pair of electrons between the iodine atoms in order to gain a stable arrangement of 8 electrons in its outer shell. It is sharing them, so it's a covalent bond as a single iodine atom cannot be stable on its own. It's a halogen and is a single covalently-bonded diatomic molecule.
Similarly, take oxygen. IT needs two pairs of electrons just so it can reach a stable outer shell of 8 electrons. If it doesn't then it cannot be stabilised so it must be bonded with another oxygen atom and share two electrons.
I would say D: 2 and 4.
The first line of the question is very important. X reacts with Y to form a gas.
For 2, we let the gas escape and measure the change in mass during the reaction.
For 4, we capture the change in volume of gas during the reaction.
1 does not work: some of the gas escapes through the cotton and the gas captured is not recorded correctly.
3 does not work: the gas is trapped and the mass balance does not record a change in mass.
Answer:
1. A substance 2. Valence
Explanation:
Answer:
Explanation:
Molarity is a measure of concentration in moles per liter.
We know the molarity is 2.0 M CaCl. However, we can convert the units to make the problem easier. 1 molar (M) is equal to 1 mole per liter. A 2.0 M CaCl molarity is equal to 2.0 moles of CaCl per liter.
We also know there are 250 milliliters of solution. however, we need to find the liters. Remember that 1 liter contains 1000 milliliters.
Now we can substitute the values we know into the formula. Since moles of solute are unknown, we can use x.
- molarity= 2.0 mol CaCl/ L
- moles of solute =x
- liters of solution = 0.250 L
Since we are solving for x (the moles of solute), we need to isolate the variable. It is being divided by 0.250 L. The inverse of division is multiplication, so we multiply both sides by 0.250 L.
The units of liters (L) cancel.
There are <u>0.5 moles of solute</u> in 250 milliliters of a 2.0 M solution.