Question

some atoms of the same element have a different number of ______ in their nucleus. these are called isotopes. protons electrons neutrons orbits which of the following matches of group number and common name is incorrect? group 7 - transition metals group 2 - alkali earth metals group 2 - actinides group 18 - noble gases determine the products that form in the double displacement reaction between potassium sulfate and calcium chloride. write the word equation and a balanced chemical equation.

Explanation:

Question 1:

Isotopes are atoms of the same element with different numbers of neutrons in their nucleus. Protons define the element, electrons are outside the nucleus, and orbits are related to electron - movement, not the nucleus composition for isotopes.

Question 2:

Group 2 elements are alkali - earth metals, Group 18 are noble gases. Transition metals are in groups 3 - 12. Actinides are in the f - block and not in Group 2.

Question 3:

Step1: Write the reactants

Potassium sulfate ($K_2SO_4$) and calcium chloride ($CaCl_2$) are the reactants.

Step2: Predict the products by double - displacement

The cations and anions switch places. The products are potassium chloride ($KCl$) and calcium sulfate ($CaSO_4$).

Step3: Write the word equation

Potassium sulfate + calcium chloride → potassium chloride + calcium sulfate

Step4: Write the balanced chemical equation

$K_2SO_4(aq)+CaCl_2(aq)
ightarrow 2KCl(aq)+CaSO_4(s)$

Answer:

Question 1: C. neutrons
Question 2: C. Group 2 - actinides
Question 3:
Word equation: Potassium sulfate + calcium chloride → potassium chloride + calcium sulfate
Balanced chemical equation: $K_2SO_4(aq)+CaCl_2(aq)
ightarrow 2KCl(aq)+CaSO_4(s)$