1 elements
2 they have same number of valence electrons
3 period
Change in energy is E=hc/wavelength of emitted photon
Answer:
C. NaHCO3 → Na2CO3 + H2O + CO2
Explanation:
» For a balanced equation, the number of atoms of reactants and products must be equal.
» In equation C, the reactant side has one sodium atom while ptoduct side has 2 sodium atoms.
» The balanced equations mus be;

Answer:
Epithelial tissues act as coverings, controlling the movement of materials across their surface. Connective tissue binds the various parts of the body together, providing support and protection. Muscle tissue allows the body to move and nervous tissues functions in communication.
Explanation:
Answer:
Density = mass / volume.
If this is an ideal gas then 1mol will take up 22.4L of volume (fact about ideal gases you should remember)
Since you have 1mol then you know the volume of the gas that you have (22.4L)
Now, just convert 1mol of CO to grams.The ptable tells you that the mass of 1 mol of C is 12g and the mass of 1 mol of O is 16g. So the mass of 1 mol of CO is......... :):)
Now you have the mass and the volume, so just divide :) enjoy