Answer:
A rolling ball eventually slows down and comes to a stop
Answer:
1.8g/cm³
Explanation:
Density is defined as the ratio of the mass of a substance and the space this subtance occupies. It is usually given in g/cm³.
The mass of the block is 30g.
The volume this mass occupies is 1.5cm × 4.8cm × 2.3cm = 16.56cm³.
The density is:
30g / 16.56cm³ =
<h3>1.8g/cm³</h3>
Answer: He should add a single dot below the symbol to correct the electron dot diagram of an aluminium atom.
Explanation: Electron dot structures are the structures in which valence electrons around an atom are shown. The electrons are represented as dots in these structures.
Aluminium is the 13th element of the periodic table.
Electronic configuration of Aluminium is given by:

Valence electrons of aluminium = 3
In the given image, 2 valence electrons are shown and total number of valence electrons are 3. So, in order to correct the diagram, he should add a single electron below the symbol.
Answer:
-100.125
Explanation:
We are given
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (l) △H = -890.0 kJ/mol
The given information is for complete reaction
we have 1.8grams of Methane
Molar mass of CH4 = 16
No of moles of Methane = 1.8/ 16
= 0.1125
So the amount of the heat will be released from the amount of the methane
Q = No of moles*( -890.0 kJ/mol)
= 0.1125*(-890)
= -100.125kJ/mole
Therefore the amount of Energy released from 1.8 grams of methane is equal to -100.125