Answer:
I really dont know i just guessed :(
Explanation:
Explanation:
The dimensions of a standard backpack is 30cm x 30cm x 40cm
The mass of an average student is 70 kg
We know that, the density of gold is 19.3 g/cm³.
Let m be the mass of the backpack. So,

An average student has a mass of 70 kg. If we compare the mass of student and mass of backpack, we find that the backpack is 10 times of the mass of the student.
Answer: 159 grams
Explanation:
Copper (ii) oxide has the chemical formula CuO.
Now given that:
Mass of CuO in grams = ? (let unknown value be Z)
Number of moles = 2.00 moles
Molar mass of CuO = ?
For the molar mass of CuO: Atomic mass of Copper = 63.5g ; Oxygen = 16g
= 63.5g + 16g
= 79.5 g/mol
Apply the formula:
Number of molecules = (mass in grams/molar mass)
2.00 moles = (Z / 79.5 g/mol)
Z = 79.5 g/mol x 2.00 moles
Z = 159g
Thus, there are 159 grams in 2.00 moles of copper (ii) oxide
Answer:
Bleach and seawater are identified wrong.
Explanation:
Acids have an pH that is lower than 7 and bases have a pH of higher than 7 and (pH 7 is neutral)
We can observe from the table that bleach has a pH of 13 which is higher than 7 and shows basic characteristics
As for seawater the table shows it has a pH of 8 which is also a base. Therefore the answer is 3rd option "Bleach and seawater should be identified as bases".
francium , in the Periodic table the atomic radius increases from top to bottom in a group, and decreases from left to right across a period. making helium is the smallest element, and francium the largest.