Answer:
A. NaHCO₃
Explanation:
NaHCO₃ ⇒ NaOH + H₂CO₃
NaOH is a strong base and H₂CO₃ is a weak acid. Therefore, NaHCO₃ is a salt of a strong base-weak acid reaction. The salt is basic because carbonic acid (H₂CO₃) is a weak acid so it remains undissociated. So, there is a presence of additional OH⁻ ions that makes the solution basic.
Hope that helps.
(4) Zirconium
This element is often used in the chemical production field, and as implants due to its high chemical resistance and stability.
Explanation:
When we have direct sunlight, the temperature is higher compared to indirect sunlight.
Direct sunlight is usually overhead whereas indirect sunlight is at an angle to the surface.
- Direct sunlight impacts the surface with more energy concentrated on a smaller surface area.
- This warms the surface more.
- Indirect sunlight is diffuse and spreads over a wider area.
- This leads to a reduction in temperature.
Answer:
13.20 cm/s is the rate at which the water level is rising when the water level is 4 cm.
Explanation:
Length of the base = l
Width of the base = w
Height of the pyramid = h
Volume of the pyramid = 
We have:
Rate at which water is filled in cube = 
Square based pyramid:
l = 6 cm, w = 6 cm, h = 13 cm
Volume of the square based pyramid = V
Differentiating V with respect to dt:
Putting, h = 4 cm
13.20 cm/s is the rate at which the water level is rising when the water level is 4 cm.
