Out of the following given choices;
A. the size of the atoms in a substance
B. the number of molecules in a substance
C. the position of the electrons on the outer valence shells
D. the balance between intermolecular forces and kinetic energy
The answer is D. The kinetic energy of the molecules is determines by the temperatures of the substance. The higher the temperatures, the higher the kinetic energy of the molecules. The molecules subsequently move and collide with higher energies and overcome intermolecular forces. This allows the substance to changes state from solid to liquid and eventually to gas (with increasing kinetic energy).
B) Polaris
C) Both A & B
D) The north pole
Answer is: 4) form an aqueous solution.
Physical property can be observed and measured without any changes in molecular composition. The same substance is present before and after the change. Making aqueous solution is physical change (solvatation).
Element reactions with acids, oxygen and chlorine are chemical change (chemical reaction combustion), because new substances are formed, the atoms are rearranged and the reaction is followed by an energy change (exothermic reaction because energy is released).
Answer:
Explanation:
Rusting of iron occurs during the reaction of iron and oxygen in the presence of moisture to form hydrous iron (III) oxide, which is a reddish brown substance.
By virtue of this, the atoms which are reactants in the redox reaction would e oxygen and iron.
I hope this was clear and easy to understand.
like and rate <3
an element
a compound
Answer:
≈ 0.70 g/cm³ (answer rounded up to 2 decimal places)
Explanation:
The mass of empty cylinder is 20g
The mass of water filling the cylinder = 30g - 20g = 10g
The mass of unknown liquid filling the cylinder = 27g - 20g = 7g
Density of water = 997 kg/m³
Converting this density to g/cm³ we get;
1kg = 1000g , 1m³ = 1000000cm³
So density = g/cm³ = 0.997 g/cm³
So the volume of water occupied by 10g is;
10 × 0.997 = 9.97 cm³
This volume is also occupied by 7g of the unknown liquid.
Density = mass/volume
Density of the unknown liquid = 7g ÷ 9.97cm³ = 0.702106319 g/cm³ ≈ 0.70 g/cm³ (answer rounded up to 2 decimal places)