Answer:
7.32g of HNO3 are required.
Explanation:
1st) From the balanced reaction we know that 2 moles of HNO3 react with 1 mole of Ca(OH)2 to produce 2 moles of H2O and 1 mole of Ca(NO3)2.
From this, we find that the relation between HNO3 and Ca(OH)2 is that 2 moles of HNO3 react with 1 mole of Ca(OH)2.
2nd) This is the order of the relations that we have to use in the equation to calculate the grams of nitric acid:
• starting with the 4.30 grams of Ca(OH)2.
,
• using the molar mass of Ca(OH)2 (74g/mol).
,
• relation of the 2 moles of HNO3 that react with 1 mole of Ca(OH)2 .
,
• using the molar mass of HNO3 (63.02g/mol).
So, 7.32g of HNO3 are required.
20 g O2 x 1 mol O2/32 g O = 0.625 mol O2
Answer:
ρ = 1.08 g/cm³
Explanation:
Step 1: Given data
Mass of the substance (m): 21.112 g
Volume of the substance (V): 19.5 cm³
Step 2: Calculate the density of the substance
The density (ρ) of a substance is equal to its mass divided by its volume.
ρ = m / V
ρ = 21.112 g / 19.5 cm³
ρ = 1.08 g/cm³
The density of the substance is 1.08 g/cm³.
Answer:
Rutherford was the first scientist who proposed the nuclear model of the atom. According to his atomic model, most of the space of an atom is empty, while the nucleus containing protons and neutrons lie at the center of the atom while electrons revolve around nucleus in definite orbits.
If we talk about studies of some other scientists like Dalton, Neil Bohr and JJ Thomson, they all are compatible with Rutherford's results to a large extent.
For example: Dalton's atomic model assumed that atoms of any substance are similar in size and atoms react to form compounds. Rutherford's concept indicated that atoms contain electrons and they are in a specific number which can be shared to form compounds.
If we talk about Bohr's model, it states that electrons revolve around nucleus in specific shells, this again is compatible with Rutherford's results which gave the concept of shells.
If we talk about Thomson's Plum pudding model, that describe atom as negative particles floating within a soup of diffuse positive charge. This is also compatible with the results of Rutherford that state that negative electrons surround positive nucleus.
Rutherford's model was best atomic model but still it took help from many previous studies and therefore was compatible with the results of old models.
Hope it help!
