Explanation

Chemical Name: Sodium Carbonate 

Chemical Formula: Na₂CO₃ 

Common Names: Sodium carbonate, washing soda, calcined soda, disodium carbonate 

Characteristics:

It is a white, odorless solid that is water-soluble. 

When dissolved in water, it forms a moderately alkaline solution. 

It is a strong base. 

Explanation

Temporary hardness caused by calcium and magnesium bicarbonates is removed by boiling, 

A process that converts the soluble bicarbonates into insoluble carbonates or hydroxides, which then precipitate out of the water.

These precipitates, such as calcium carbonate and magnesium hydroxide, can be filtered out, leaving softer water. 

Explanation

A steady-state system refers to a system where properties remain constant over time. 

In a steady-state system, properties such as temperature, pressure, and composition remain constant despite ongoing processes within the system.

This means that the input and output rates of energy and mass are balanced, resulting in no net change over time. 

Explanation

N atomic mass =14, H=1×3=3; total=17; %N = (14/17) ×100 ≈ 82%.

Explanation

Radians = degrees × (π/180); 45 × π/180 = π/4.

Explanation

Latent heat refers to the energy absorbed or released by a substance during a phase change (like solid to liquid or liquid to gas) without a temperature change. 

Explanation

Standard Temperature and Pressure (STP) refers to defined reference conditions used to compare gas properties and for scientific calculations.

Typically set at 0°C (273.15 K) for temperature and 1 atm (101.325 kPa) for pressure.

However, the International Union of Pure and Applied Chemistry (IUPAC) has a slightly different definition for STP,

Using 100 kPa (1 bar) for pressure instead of 1 atm. 

Explanation

Convert 37 1/2 = 75/2 = 37.5;

number of 1/8 in 37.5 = 37.5 ÷ (1/8) = 37.5 × 8 = 300.

Explanation

Lower pH means more acidic:

A decrease in pH indicates an increase in the concentration of hydrogen ions ([H+]) in the solution. 

Stronger acid:

The closer the pH is to zero, the more acidic the solution is, meaning it's a stronger acid. 

Logarithmic scale:

Each whole number decrease on the pH scale represents a 10-fold increase in acidity. 

pH < 7 is acidic:

Substances with a pH below 7 are considered acidic. 

pH = 7 is neutral:

Pure water at 25°C has a pH of 7 and is neutral. 

Higher pH is basic:

Solutions with a pH greater than 7 are basic or alkaline. 

Explanation

In irregular (diffused) reflection, light rays hit a rough surface.

This causes them to reflect in different directions and angles.