The exact pH of washing powder can vary depending on the brand and specific ingredients. However, most washing powders contain alkaline substances such as:

* Sodium carbonate (washing soda): This is a strong alkali with a pH of around 11.5.

* Sodium bicarbonate (baking soda): This is a milder alkali with a pH of around 8.3.

* Sodium silicate: This is an alkali that helps soften water.

The alkaline nature of washing powder helps to break down dirt and grime, which are often acidic. It also lifts and suspends dirt in the wash water so it can be rinsed away.

Note: Some washing powders may contain acids to enhance their cleaning power or for specific purposes, such as stain removal. However, the overall pH of the powder will still be alkaline.