<span>Endothermic reactions take in heat from the environment in order to react while exothermic reactions release heat during the reaction. For this, D must be true as the products have less energy because they have released heat during the reaction. A and C are incorrect because they products and reactants are equal and B is wrong because the energy of the products would be more as the reaction took in heat.</span>
Answer:
C
Explanation:
Rust is a chemical change (reaction) all of the other options only change the state meaning that it is a physical reaction.
The correct name of the compound Mn3(PO4)2 is definitely the last option represented above <span>D. manganese(II) phosphate. I am pretty sure this answer will help you
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Answer:Properties that help geologists identify a mineral in a rock are: color, hardness, luster, crystal forms, density, and cleavage. Crystal form, cleavage, and hardness are determined primarily by the crystal structure at the atomic level. Color and density are determined primarily by the chemical composition.
The mass of copper (Cu) is 63.55 grams.
Remember that 6.022×10²³ atoms = 1 mol (Avogadro's number).
To get from grams to atoms, you need to multiply 1.2 grams of copper × 1 mol of copper × 6.022×10²³ atoms of copper and divide it by 63.54 grams of copper and 1 mol of copper.
This will cancel out the grams and moles to give you the answer in atoms of copper!
1.2 grams of copper × 1 mol of copper × 6.022×10²³ atoms of copper
63.54 grams of copper x 1 mol of copper
= 1.137×10²² atoms of copper
= round to 2 sig figs: 1.1×10²² atoms of copper
