What is the percent by mass of oxygen in propanal, CH3CH2CHO? (1) 10.0% (3) 38.1%

(2) 27.6% (4) 62.1%

Which statement describes a chemical property of iron? Iron oxidizes. Iron is a solid at STP. Iron melts. Iron is attracted to a magnet.

Which kingdom does a multicellular living organism most likely belong to? Animalia Archaebacteria Bacteria Eukarya

List the bonding pairs H and I; S and O; K and Br; Si and Cl, H and F; Se and S; C and H in order of increasing covalent character. 1. (S, O) < (Se, S) < (C, H) = (H, I) = (H, F) < (Si, Cl) < (K, Br) 2.

Which statement about the electron-cloud model is true? It is the currently accepted atomic model. It can easily be replaced by existing models. It specifies the location and momentum of an electron.

Identify the housing option that has the lowest maintenance cost a single-family home b condominium c mobile home or d apartment

Which of the following determines the strength of the force and gravity between two objects? choose all that apply A) the speeds of the objects B) the masses of the objects C) the distance between the objects D) the volume of the objects

The opposite of vaporization

6.8. Liquid methyl ethyl ketone (MEK) is introduced into a vessel containing air. The system temperature is increased to 55°C, and the vessel contents reach equilibrium with some MEK remaining in the liquid state.

What is the pH of a solution that has a H + concentration equal to 1.7 x 10-5 M? 5.20 0.22 10.20 4.77

4 Compared to the energy and charge of the electrons in the first shell of a Be atom, the electrons in the second shell of this atom have (1) less energy and the same charge (2) less energy and a different charge (3) more energy and the same charge