Find the mass of 0.89 moles of magnesium chloride, mgcl2

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If 1.63 times 10 negative 4 of helium dissolves in 100.0g of water, what is the concentration in parts per million

When 225mg of anthracene, c14h10(s), was burned in a bomb calorimeter the temperature rose by 1.75k. calculate the calorimeter constant. by how much will the temperature rise when 125mg of phenol, c6h5oh(s), is burned in the calorimeter under the same conditions? (δch< (c14h10,s)=–7061 kj mol−1.)