Answer:
25.2 kJ
Explanation:
The full question can be found in the image linked to this response.
It's important to highlight that the heat absorbed by the 2.00 L of water for increasing its temperature from the beginning to the end comes solely from the burning of benzoic acid, as there are no heat transfers to the container or the surroundings.
To find the heat released from benzoic acid combustion, we simply measure the heat needed to warm the water.
Q = mCΔT
To find the mass of the water,
Density = (mass)/(volume)
Mass = Density × volume
Density = 1 g/mL
Volume = 2.00 L = 2000 mL
Mass = 1 × 2000 = 2000 g
C = specific heat of water = 4.2 J/g.°C
ΔT = (final temperature) - (Initial temperature)
<pAccording to the graph,
Final water temperature = 25°C
Initial water temperature = 22°C
ΔT = 25 - 22 = 3°C
Q = (2000×4.2×3) = 25,200 J = 25.2 kJ
Hope this Helps!!!
Answer:
Calcium's atomic radius is roughly 175 pm.
Explanation:
We know that magnesium has an atomic radius of 150 pm.
The atomic radius of strontium measures 200 pm.
Since calcium's position is between magnesium and strontium in group 2 of the periodic table, its atomic radius should be roughly averaged between magnesium's and strontium's atomic radii because atomic radius is not constant.
Thus;
Calcium's atomic radius is approximately calculated as follows;
The average atomic radius is (200 + 150)/2 = 175 pm.
Answer:
2.5 g of platinum
Explanation:
A catalyst is a substance added to a reaction to enhance the reaction speed. It does not undergo any change during the reaction, meaning it remains unchanged after the reaction concludes. The role of a catalyst is to provide an alternative pathway for the reaction by reducing the activation energy required. Therefore, a catalyzed reaction occurs more rapidly and requires less energy compared to an uncatalyzed one.
Since catalysts do not get involved in reactions and retain their mass post-reaction, the amount of platinum will stay the same (2.5g). The mass can only alter if a substance participates in the chemical process. Thus, this is the response.
Explanation:
Elements provided:
F, Sr, P, Ca, O, Br, Rb, Sb, Li, S
Elements sharing similar reactivity belong to the same group in the periodic table, indicating that those in the same column exhibit comparable reactivity. Here are the identified groupings:
Li and Rb are alkali metals in group 1
Ca and Sr are alkaline earth metals in group 2
F and Br are halogens in group 7
O and S belong to group 6
P and Sb are classified in group 5 of the periodic table
Thus, these classifications illustrate elements with the same chemical characteristics.
Answer: Rearrange the lone pairs of electrons from the outer atom(s) to create double or triple bonds with the central atom.
Explanation:
