Answer:
The correct answer is a
Explanation:
The formula for density is mass ÷ volume. Hence, a balance is required to determine the mass while a measuring/graduated cylinder is required to determine the volume.
The ideal measuring cylinder and balance to be used should have an uncertainty of just 0.1 ml and 0.1 g respectively. This reduces the chances of the answer gotten from the formula above to be more than 3 significant figures.
For example, if the volume to be used is 4.0 ml and the mass of this volume is 3.5 g, the density will be
Density = 3.5 ÷ 4
Density = 0.875 g/cm³ or 0.875 g/ml
NOTE that cm³ is the same measurement as mL
The answer above is in 3 significant figures
Test are not directly used to make measurements, I mean you could use them to put 4 mL of a substance in, but not to measure out 4 mL, like with graduated cylinders. Rulers can be used to measure the length of something, like the number of inches. And a thermometer will help you measure the temperature of something.
Answer:
Six electrons are transferred in the formation of Al₂O₃.
Explanation:
Aluminium metal and Oxygen react to form Al₂O₃ as,
2 Al + 3/2 O₂ → Al₂O₃
Oxidation number of Al on left hand side is zero, while than on right hand side in Al₂O₃ is +3. Means it has lost 3 electrons per one atom and six electrons per two atoms. Also, the oxidation number of O at left hand side in O₂ is zero, while that in Al₂O₃ it is -2 per atom and -6 per 3 atoms.
So, two Al atoms have lost 6 electrons and 3 O atoms have gained six electrons.
Answer:
Hello!
Gold is a chemical element with symbol Au (from Latin: aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal and a group 11 element.
So in short, the Correct Answer will be (D) an Element.
Hope that Helps! Have A Wonderful Day! ☺
Explanation:
Answer:
two hydrogen atoms and one oxygen atom
Explanation: