<span>The gas phosphine (PH3) is used as a fumigant to protect stored grain and other durable produce from pests. Phosphine is generated where it is to be used by adding water to aluminum phosphide or magnesium phosphide. Give formulas for these two phosphides.
</span>Al₂P₃ + 3H₂O → 3PH₃ + Al₂O₃
MgP + H₂O → PH₃ + MgO
The answer is; The spectrum of a star shifts towards the blue region when the star moves towards Earth.
This is referred to as the Doppler shift effect. As the star moves closer to the observer, the wavelength of light it produces is ‘compressed’ hence changing its relative frequency (just like the pitch of the siren of an ambulance approaching you).
Answer:
342.8 kJ are absorbed
Explanation:
In the reaction:
4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(l) ΔH° = 1168 kJ
<em>As ΔH > 0, the heat is absorbed. Also, when 4 moles of NH3 are involved in the reaction, there are absorbed 1168 kJ</em>.
Having this in mind, moles of NH3 in 20.00g are:
20.00g × (1mol / 17.0307g) = <em>1.174 moles</em>
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Thus, 1.174 moles of NH3 absorbed:
1.174 moles × (1168 kJ / 4 moles) = <em>342.8 kJ are absorbed</em>.
Answer:
Physical property: Any characteristic that can be determined without changing the substance's chemical identity. Chemical property: Any characteristic that can be determined only by changing a substance's molecular structure.
Explanation:
Physical properties are something that is reverseable or has no change visible. Chemical properties are something that is NOT reverseable.
Chemical: Gas forming or Color Changing. (ETC.)
Bikes that are kept outside are not used as often, speeding up the chemical reaction of metal rusting.
Heat energy from the sun slows down the chemical reaction of the metal rusting.
Moisture and oxygen cause oxidation, which speeds up the chemical reaction of the metal rusting.
Wind energy outside speeds up the chemical reaction of the metal rusting.
