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What is the new freezing point (in °C) of a 1.50m aqueous solution of CaCl2 ? Hint: The molal freezing point depression constant (Kf) of water is 1.86°C/m.

125 g of Cu(NO3)2 is added to enough water to produce 485 mL of solution. What is the molarity (in M) of this solution? Hint: molar mass copper (II) nitrate = 187.57 g/mol

For the diethyl azodicarboxylate molecule (DEAD) below, the hybridization for arrow indicated oxygen atom is _______ and there is/are  _______  pi (π) bond(s) in the structure. Hint:  Not all H and C are written out.  Consider the bonded hydrogens and the lone pairs that are not depicted on the structure but may needed to complete an octet.  

Quick breads and biscuits use the thermal decomposition of sodium bicarbonate as their source of gas for rapid inflation instead of yeast to make the dough rise. The chemical reaction follows:                                              2 NaHCO3 (s) → Na2CO3 (s) + CO2(g) + H2O (g) What mass (g) of NaHCO3 is required to provide 1.75 L of CO2 gas at 428 K and 1.00 atm? Hint:  molar mass of NaHCO3 is 84.01 g/mol 

Hydrogen gas reacts with chlorine gas to form hydrogen chloride according to the following reaction: H2 (g) + Cl₂ (g) → 2 HCl (g) The molecular-level diagram shows three H2  molecules and four Cl2 molecules before a reaction occurs. What is the limiting reactant, and how many HCl molecules should form?

Which particle depicted below would have the following complete chemical symbol?

What is the new boiling point (in °C) of a 2.10m aqueous solution of MgCl2? Hint: The molal boiling point elevation constant (Kb) of water is 0.512°C/m.

Hydrogen gas reacts with chlorine gas to form hydrogen chloride according to the following reaction: H2 (g) + Cl₂ (g) → 2 HCl (g) The molecular-level diagram shows six H2  molecules and four Cl2 molecules before a reaction occurs. What is the limiting reactant, and how many HCl molecules should form?

At the same temperature, hydrogen gas (H2) molecules move faster on average than oxygen gas (O2) molecules. According to the Kinetic Molecular Theory, why does this occur?

Solutions of Na2CO3 (aq) and MgCl2 (aq) are mixed together. What is/are the spectator ion(s) in this reaction? Hint:  Write the molecular and complete ionic equations.