{b} In experiment B. the iron filings weighed 2.0g at the beginning of the experiment
and the iron sulphide produced weighed 2.8g.
Explain this increase in mass.

Explanation:

The increase in mass is because the iron fillings have combined with a sulfide to produce iron sulfide and so the mass will increase.

In such a reaction like this, the mass of the reactants must be conserved. By so doing, the mass of reactants and products must be the same.

When two substances combine together, their masses added up to that of the individual masses. This helps to conserve the mass.

the awnser is group 12

warm front forms when a moist, warm air mass slides up and over a cold air mass. as the warm air mass rises, it condenses into a broad area of clouds. a warm front brings gentle rain or light snow, followed by warmer, milder weather.

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