Answer is: the density of the material is 0.8 g/cm³.
m(material) = 6.75 g; mass of unknown material.
V(material) = 9 cm³; volume of unknown material.
d(material) = m(material) ÷ V(material).
d(material) = 6.75 g ÷ 9 cm³.
d(material) = 0.75 g/cm³; density of unknown material.
Answer:
Geiger counter
Explanation:
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(2) equal to the number of protons gained
(3) less than the number of electrons gained
(4) less than the number or protons gained
Convert 3.00 moles of MgO to moles of Fe2O3
71.8 g of iron (III) oxide (Fe₂O₃) were produced from 3 moles of magnesium oxide (MgO).
Explanation:
We have the following chemical reaction:
2 FeCl₃ + 3 MgO → Fe₂O₃ + 3 MgCl₂
We see from the chemical reaction that 3 moles of magnesium oxide (MgO) will produce 1 mole of iron (III) oxide (Fe₂O₃).
number of moles = mass / molar weight
mass = number of moles × molar weight
mass of Fe₂O₃ = 1 × 71.8 = 71.8 g
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number of moles
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The mass of protons and neutrons are both 1 amu (atomic mass unit). The mass of the electron is 0.00054. Therefore, when determining the isotopes when given mass, you only focus on the neutrons as they are the subatomic particles that are significantly affecting the atomic mass.
B) The element is most likely from Group 2A or 3A and in period 2 or 3.
C) The element is most likely from Group 4A or 5A and in period 4 or 5.
D) The element is most likely from Group 6A or 7A and in period 6 or 7
Answer:
The list of answer choices is wrong.
The correct list is:
A) The element is most likely from Group 1A or 2A and in period 1 or 2.
B) The element is most likely from Group 2A or 3A and in period 6 or 7.
C) The element is most likely from Group 4A or 5A and in period 4 or 5.
D) The element is most likely from Group 6A or 7A and in period 2 or 3.
The correct answer is:
Explanation:
The ionization energy increases from left to right on the periodic table. So the elements with higer ionization energies are in the right end of the table. The right most columns are 6A (16) and 7A(17). The column 8A (18) which is that of the noble gases is not normally taken into acccount for this predictions because noble gases are nearly inert.
Hence, the fact that the statement indicates high ionization energy suggests that the element is most likely from group 6A or 7A.
The atomic radius increases from top to bottom, so the smallest elements are in the top rows, which is the periods 1, 2, or 3. The period 1 only has two elements, hydrogen in group 1 and helium in group 8A, so they are not considered in the choices. Thus, that leaves you with the periods 2 or 3.
Adding the two considerations, the conclusion is that the element is most likely from group 6A or 7A and in period 2 or 3.
Answer:
Explanation:
The answer is A) The element is most likely from Group 1A or 2A and in period 1 or 2
Answer:the reaction arrow is used most frequently and indicates a reaction occurring from the reactants to the products. The arrow's head points in the direction the reaction proceeds in.