Answer is: the mass of a block of magnesium is 177.75 grams.
m(Fe) = 826 g.
d(Fe) = 7.9 g/cm³.
1) Calculate volume of iron and magnesium:
d(Fe) = m(Fe) ÷ V(Fe).
V(Fe) = m(Fe) ÷ d(Fe).
V(Fe) = 826 g ÷ 7.9 g/cm³.
V(Fe) = V(Mg) = 104.56 cm³.
2) Calculate mass of magnesium:
m(Mg) = V(Mg) · d(Mg).
m(Mg) = 104.56 g/cm³ · 1.7 g/cm³.
m(Mg) = 177.75 g.
Answer:
Conduct electricity when they are molten, while covalent compounds usually do not conduct electricity when they are molten.
Answer:
Heat lost to the surroundings
Heat lost to the thermometer
Explanation:
All changes in heat, or energy, can be explained. Many of the reactions or changes we see in the world involve the conversion of energy. For example as we heat up a substance (eg. water), the amount of energy we put in should give us an exact temperature. However, this is a "perfect world" scenario, and does not occur in real life. Whenever heat is added to a substance like water, we always need to account for the energy that is going to be lost. For example, heat lost to evaporation or even the effect of measuring the temperature with a thermometer (the introduction of anything including a thermometer will affect the temperature).
Answer:
0.0164 g
Explanation:
Let's consider the reduction of silver (I) to silver that occurs in the cathode during the electroplating.
Ag⁺(aq) + 1 e⁻ → Ag(s)
We can establish the following relations.
- 1 A = 1 C/s
- The charge of 1 mole of electrons is 96,468 C (Faraday's constant)
- 1 mole of Ag(s) is deposited when 1 mole of electrons circulate.
- The molar mass of silver is 107.87 g/mol
The mass of silver deposited when a current of 0.770 A circulates during 19.0 seconds is:
Answer is: D. It is not sodium bicarbonate.
Balanced chemical reaction of heating sodium bicarbonate: 2NaHCO₃ → Na₂CO₃ + CO₂ + H₂O.
This is chemical change (chemical reaction), because new substances are formed (sodium carbonate, carbon(IV) oxide and water), the atoms are rearranged, so there is no sodium bicarbonate (NaHCO₃) in the test tube.
