Answer:
false
Explanation:
It is a physical reaction because it is being heated.
For 1 mole of any substance, there are 6.02214086 × 10^<span>23 particles (atoms, molecules, ions, etc. depending on the substance)
So, for 1 mole of water, there are </span>6.02214086 × 10^23 water particles, and so on
So, in 1 mole of Lithium, there are 6.02214086 × 10^23 Lithium atoms
Answer:
Explanation:
A physical change occurs when only the physical properties change. They are generally reversible and no new substances are formed.
However, in a chemical change, the chemical structures and properties change, plus new substances are formed.
Let's analyze each answer choice.
1. Change in state of matter
The state of matter is a physical property, so this is a physical change.
2. Precipitate was formed
A precipitate is a solid formed in a liquid solution. This is a new substance and a chemical change.
3. Unexpected change in odor.
A change in odor is a sign of chemical change.
4. Formation of bubbles
Bubbles signify the formation of gas or a new substance.
So, the best answer choice is <u>A. change in state of matter</u>
Answer:
3.6124 m/kg
Explanation:
Molality is calculated as moles of solute (mol) divided by kilogram of solvent (kg). Here, we can find these numbers by using the 35.4%, which gives us 35.4 g of H3PO4 and 100 g of solution to work with.
To go from grams to moles for the phosphoric acid, you need to find the molar mass of the compound or element and divide the grams of the compound or element by that molar mass.
Here, the molar mass for phosphoric acid is 97.9952 g/mol. The equation would look like this:
35.4 g x 1 mol / 97.9952 g = 0.3612422 mol
Next, the 100 g of solvent can easily be converted to 0.1 kg of solvent.
To find the molality, divide the moles of solute and kilograms of solution.
0.3612422 mol / 0.1 kg = 3.6124 m/kg
True. Any cosmetic containing paraffin wax, benzene, mineral oil, PEG, DEA, MEA, the suffix ethyl- or propyl-, etc. About 95% of fragrances contain petrochemicals.
