Answer:
4.1 moles
Explanation:
Applying
PV = nRT................ equation 1
Where P = pressure, V = volume, n = number of moles, R = molar gas constant, T = Temperature.
make n the subject of the equation
n = PV/RT.............. Equation 2
From the question,
Given: V = 35 L , P = 2.8 atm, T = 15 °C = (15+273) = 288 K, R = 0.083 L.atm/K.mol
Substitute these values into equation 2
n = (35×2.8)/(0.083×288)
n = 4.1 moles
The density of Ca will be between that of Mg and Sr
Explanation:
Ca, Mg and Sr are group II elements. They are called alkali earth metals. The correct order of the elements in this group are: Be, Mg, Ca, Sr, Ba and Ra.
Density is an intensive property of matter which describes the amount of matter(mass) per volume of a substance.
- Density varies proportionally with mass. The higher the mass, the higher its density.
- On the periodic table, atomic mass which the number of protons and neutrons in the nucleus of an atom increases down the group.
- This implies a progradation in the value of density down the group. Therefore one expects that the value of density of Ca will fall between that of Mg and Sr. It cannot be more than 2.6g/cm³ nor less than 1.74g/cm³.
Learn more:
density brainly.com/question/2658982
mass number brainly.com/question/2597088
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For an object to conduct electricity it should have free or delocalised electrons that are free to pass the charge and hence take part in conducting electricity.
From the given choices
Chlorine is a halogen existing as a diatomic gas. Iodine too is a halogen and 2 Iodine atoms held together by covalent bond. Cl - Cl bonds and I-I bonds are covalent bonds. the outer electrons of Cl and I take part in covalent bonds therefore they are fixed and not free to move about. therefore no free electrons to conduct electricity.
Sulfur is a solid that too is held together by covalent bonds so it does not have free electrons to conduct electricity.
Silver is a metal and a general property of metals are their ability to conduct electricity.
metal structure are metal ions tightly packed together. when the metal atoms are tightly packed their valence electrons are removed and delocalised. Positively charged metal ions are embedded in a sea of delocalised electrons.
therefore there are delocalised electrons that can conduct electricity
answer is 3) silver
Answer: Anna stated that ionic compounds have high melting point and low boiling point. The error in the statement is that ionic compound have low boiling point, instead ionic compounds have high boiling point, because in an ionic compound, the force of attraction working between two ions is very strong and hence the bonds present are very strong, and a lot of energy is needed to break them
