Explanation

Sulphur powder is commonly found as a bright yellow solid.

It is non-metallic.

It is used in medicines, fertilizers, and chemicals.

Explanation

Let's calculate the number of protons, neutrons, and electrons for both atoms:

³¹₁₅P (Phosphorus)

•     Protons: 15
•     Neutrons: 31 - 15 = 16
•     Electrons (neutral atom): 15

³²₁₆S (Sulfur)

•     Protons: 16
•     Neutrons: 32 - 16 = 16
•     Electrons (neutral atom): 16

Both atoms have the same number of neutrons (16).

Explanation

Metallic oxides react with water to form bases, as shown in the example:

Na₂O + H₂O → 2NaOH

This reaction demonstrates the basic nature of metallic oxides, forming a strong base (sodium hydroxide, NaOH) when reacting with water.

Explanation

A decomposition reaction involves a single compound breaking down into simpler substances.

AB → A + B is the correct format for decomposition.

Explanation

Explanation

To find the harmonic that is two octaves higher in pitch than the fundamental, we need to consider the frequency multiplication.

One octave higher = 2 × fundamental frequency

Two octaves higher = 2 × 2 × fundamental frequency = 4 × fundamental frequency

The fourth harmonic has a frequency four times the fundamental frequency, which corresponds to two octaves higher.

Explanation

Pneumatic systems are used in:

• Spray guns (to atomize and spray paint or other materials)
• Pumps (to compress and transfer fluids)
• Vacuum cleaners (to create suction and lift dust and debris)
• Dental drill or dentistry tools (to power drills, sanders, and other instruments)

Explanation

Explanation

Explanation

A reflecting telescope uses two mirrors:

1. The primary mirror (which collects and focuses light).
2. The secondary mirror (which directs the focused light to the eyepiece), to form an image of distant objects.