ch 2
How many sig figs in 389,890?
5
what type of reaction is this:
C3H8 + 5O2 --> 3CO2 + 4H2O
combustion reaction
What does an atom have to be bonded to in order to hydrogen bond?
H bonded to F,O or N
Name the molecular compound N2F2
Dinitrogen heptafluoride
How many grams are in 0.130 mols of Cl2
9.22g
solve the following and answer with the correct number of sig figs:
6.22 + 14.311
Zn(s)+CuSO4 (aq)→ZnSO4 (aq)+Cu(s)
What classification of chemical reaction does this equation represent?
single replacement reaction
dispersion forces
How many lone electrons (nonbonding electrons) are there on the central O atom of H₂O?
4 nonbonding (lone) electrons on oxygen
What are the math steps to convert grams to atoms
1. Divide the starting mass (g) by the molar mass of the compound to get mols
2. Multiply the mols by Avogadros number (6.022 x1023) to get atoms
Convert 8.77 cm to km
8.77 × 10-5 km
8.77 cm×(0.01 m/1 cm)×(1 km/1000 m)
Which of the following compounds contains the fewest number of atoms in one molecule or formula unit?
A) Al₂(SO₄)₃
B) NaHCO₃
C) (NH₄)₃PO₄
D) C₆H₁₂O₆
E) Ca₃(PO₄)₂
B) NaHCO₃ ✅
What is the name of the compound SnO₂?
Tin(IV) oxide
What is the molecular geometry of cyanide
linear
How many grams are in 0.234 moles of phosphate?
22.223 grams of phosphate
A prescription requires 0.300 mg of a medication. Each capsule contains 50 μg of the active ingredient.
How many capsules are needed to provide the prescribed dose?
6 capsules
0.300 mg×1000=300 μg
300 μg (1 capsule/50 μg)
Sucrose has the chemical formula C₁₂H₂₂O₁₁. A chemist analyzes a sample and finds that it contains 44 moles of oxygen atoms. How many moles of hydrogen atoms are present in the same sample? The molar mass of sucrose is 342.30 g/mol.
88 mols H
What is the formula and charge of bicarbonate
HCO3-
Which has a larger bond angle, CH4 or NH3
CH4 has a bone angle of 109.5
NH3 has a bone angle of >109 due to the lone pair on the nitrogen
How many mols of hydrogen are in 4g of H2O? The molar mass of H2O is 18.016 g/mol.
0.444 mols of H
A nurse gives a patient 1.5 teaspoons of medicine. The solution’s density is 1.10 g/mL, and there are 5.0 mL per teaspoon. What is the mass (in grams) of the medicine given?
8.25 g
Convert teaspoons to mL
1.5×5.0=7.5 mL
Use density formula: mass = Volume x Density
1.10×7.5=8.25 g
Which of the following compounds is predicted to have the highest boiling point: NH3 CH4 HBr
NH3
What is the formula for sodium sulfate
Na2SO4
"if a molecule contains polar bonds, it must be a polar molecule” Is this statement always true
No, Dipole charges can cancel out in a molecule
a 25 g sample of iron reacts completely with excess oxygen gas to form rust. (Fe2O3, 159.69 g/mol) according to the following equation:
4Fe + 3O2 --> 2Fe2O3
How many grams of Fe2O3 will be produced?
35.8g of Fe2O3 are produced