Cobalt has a mass number of 59 and an atomic number of 27. A student wants to create a model of a cobalt atom. Which statement about the model is correct?(1 point) Responses
The model should show 27 protons and 27 neutrons.
The model should show 27 protons and 27 neutrons.
The model should show 32 protons and 59 neutrons.
The model should show 27 protons and 32 neutrons.
7 answers
The model should show 27 protons and 32 neutrons.
In a molecule of lithium sulfide, there are two atoms of lithium and one atom of sulfur. Which statement about lithium sulfide is correct?(1 point) Responses A molecular model of lithium sulfide would have two spheres. A molecular model of lithium sulfide would have two spheres. The atoms in lithium sulfide are held together by bonds. The atoms in lithium sulfide are held together by bonds. The chemical formula for lithium sulfide is LiS2. The chemical formula for lithium sulfide is LiS 2 . Both lithium and sulfur form positive ions. Both lithium and sulfur form positive ions.
The correct statement about lithium sulfide is: "The atoms in lithium sulfide are held together by bonds."
Which element has the same number of valence electrons as bromine (Br)? (1 point) Responses selenium (Se) selenium (Se) krypton (Kr) krypton (Kr) potassium (K) potassium (K) chlorine (Cl)
The element that has the same number of valence electrons as bromine (Br) is chlorine (Cl).
Sodium reacts with chlorine to form the compound sodium chloride, or salt. The chemical formula below shows how the two elements combine into a compound. 2Na + Cl2 → 2NaCl If the total mass of the reactants is 58.44 amu, what will be the total mass of the products? (1 point) Responses 58.44 amu 58.44 amu 60 amu 60 amu 116.88 amu 116.88 amu 29.22 amu
To determine the total mass of the products in the chemical reaction of sodium with chlorine, we need to examine the coefficients in the balanced chemical equation and the molar masses of each element.
The balanced chemical equation is:
2Na + Cl2 → 2NaCl
From the equation, we can see that 2 moles of sodium (Na) react with 1 mole of chlorine (Cl2) to produce 2 moles of sodium chloride (NaCl).
The molar mass of sodium (Na) is approximately 22.99 g/mol, and the molar mass of chlorine (Cl) is approximately 35.45 g/mol.
To calculate the total mass of the products, we need to determine the total moles of sodium chloride (NaCl) produced and then multiply it by the molar mass of NaCl.
Since we have 2 moles of NaCl produced for every 2 moles of Na that react, the molar mass of NaCl can be used to calculate the total mass of the products.
The molar mass of NaCl is approximately (22.99 g/mol Na + 35.45 g/mol Cl) = 58.44 g/mol NaCl.
Therefore, the total mass of the products in this reaction will be 58.44 amu.
The balanced chemical equation is:
2Na + Cl2 → 2NaCl
From the equation, we can see that 2 moles of sodium (Na) react with 1 mole of chlorine (Cl2) to produce 2 moles of sodium chloride (NaCl).
The molar mass of sodium (Na) is approximately 22.99 g/mol, and the molar mass of chlorine (Cl) is approximately 35.45 g/mol.
To calculate the total mass of the products, we need to determine the total moles of sodium chloride (NaCl) produced and then multiply it by the molar mass of NaCl.
Since we have 2 moles of NaCl produced for every 2 moles of Na that react, the molar mass of NaCl can be used to calculate the total mass of the products.
The molar mass of NaCl is approximately (22.99 g/mol Na + 35.45 g/mol Cl) = 58.44 g/mol NaCl.
Therefore, the total mass of the products in this reaction will be 58.44 amu.
14 answers