Answer:
Replacing the powdered lead oxide with large crystals
Explanation:
The large crystals have less surface area exposed to the other reagents than the powdered lead oxide. High surface area leads to a high rate of reaction thus the products are formed faster, while a low surface area leads to a lower rate of reaction since the reagent is less exposed to the other reagents.
Answer:
Combination or synthesis
Explanation:
The reaction given below:
C + O₂ → CO₂
The reaction above is termed a synthesis or combination reaction because two substances are combining to give a product.
- A synthesis reaction involves the formation of a single product from two or more reactants.
- The driving force for such reaction is the large and negative heat of formation of the product.
Answer:
The right answer is B) evaporation
Explanation:
Transpiration occurs at the leaf surface which is the loss of water due to the evaporation. This phenomenon works as trigger of water and mineral movement above to the xylem. Due to the evaporation of water at the leaf, negative pressure is created at the surface of leaf. Tension is produced which results in the pull of water from roots up to the xylem vessels.
Explanation:
The given data for case (1) is as follows.
h = 20 cm = 0.2 m
Assuming that a rectangular slab is placed above the pipe and we will calculate the heat transfer as follows.
Q = 
where, A = area
L = length
k = thermal conductivity = 0.8 W/m
= change in temperature.
Therefore, putting the given values into the above formula as follows.
Q =
= 
= 168 W
For case (2), h = 180 cm = 1.8 m
Therefore, heat lost will be calculated as follows.
Q =
= 
= 18.67 W
Thus, we can conclude that 18.67 W heat lost if the pipe was buried at a depth of 180 cm.
Answer:
800 degrees C g, I found this answer by using the formula to find how much energy was need to melt the ice. First you figure out the temperature change of ur ice (starting temp and ur final temp), and then you times that with the mass of the water.
