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3 years ago

What conditions are required for heat transfer between states of matter to occur? In what

1 answer:

7 0

Key Concepts. The transfer of heat can occur in three ways: conduction, convection, and radiation. Heat transfer occurs between states of matter whenever a temperature difference exists and heat transfer occurs only in the direction of decreasing temperature, meaning from a hot object to a cold object.

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Convert 0.859 mg to cg. Help me plz :(

andrey2020 [161]

Answer:

0.0859

Explanation:

7 0

3 years ago

If 5.0 liters H2 (g) at STP is heated to a temperature of 985, pressure remaining constant, the new volume of the gas will be?

vlada-n [284]

Answer:

$V_2=18 \ L \ H_2$

General Formulas and Concepts:

Chemistry - Gas Laws

STP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 K
Charles' Law: $\frac{V_1}{T_1} =\frac{V_2}{T_2}$

Explanation:

Step 1: Define

Initial Volume: 5.0 L H₂ gas

Initial Temp: 273 K

Final Temp: 985 K

Final Volume: ?

Step 2: Solve for new volume

Substitute: $\frac{5 \ L \ H_2}{273 \ K} =\frac{x \ L \ H_2}{985 \ K}$
Cross-multiply: $(5 \ L \ H_2)(985 \ K) = (x \ L \ H_2)(273 \ K)$
Multiply: $4925 \ L \ H_2 \cdot K = 273x \ L \ H_2 \cdot K$
Isolate x: $18.0403 \ L \ H_2 = x$
Rewrite: $x=18.0403 \ L \ H_2$

Step 3: Check

We are given 2 sig figs as the smallest. Follow sig fig rules and round.

$18.0403 \ L \ H_2 \approx 18 \ L \ H_2$

5 0

3 years ago

Chemistry Help (Naming Oxyacids Chart)

guapka [62]

Answer:

HClO₃ /chloric acid /suffix -ic/ ClO₃⁻ (chlorate)

HClO₂/ chlorous acid/ suffix -ous/ ClO₂⁻ (chlorite)

HNO₃ /nitric acid /suffix -ic/ NO₃⁻ (nitrate)

HNO₂/ nitrous acid/ suffix -ous/ NO₂⁻ (nitrite)

Explanation:

Chlorine has 4 positive oxidation numbers to form oxyacids: +1, +3, +5 and +7.

When it uses the oxidation number +5, it forms HClO₃, which is named chloric acid, with the suffix -ic. When it loses an H⁺, it forms the oxyanion ClO₃⁻ (chlorate).

When it uses the oxidation number +3, it forms HClO₂, which is named chlorous acid, with the suffix -ous. When it loses an H⁺, it forms the oxyanion ClO₂⁻ (chlorite).

Nitrogen has 2 positive oxidation numbers to form oxyacids: +3 and +5.

When it uses the oxidation number +5, it forms HNO₃, which is named nitric acid, with the suffix -ic. When it loses an H⁺, it forms the oxyanion NO₃⁻ (nitrate).

When it uses the oxidation number +3, it forms HNO₂, which is named nitrous acid, with the suffix -ous. When it loses an H⁺, it forms the oxyanion NO₂⁻ (nitrite).

7 0

3 years ago

Use the Henderson-Hasselbalch equation and your knowledge of ionization to help you answer this question. Aspirin is a weak acid

Leya [2.2K]

Answer:

The protonated form is predominant when aspirin is absorbed more readily. The ratio of conjugate base to acid is 1 to 100.

Explanation:

Aspirin is more readily absorbed when it is protonated, that is when pH is lower than pKa (more H⁺ available in the medium). We can confirm this using Henderson-Hasselbalch equation for pH = 1.5:

$pH = pKa +log(\frac{conjugate base}{weak acid} )\\1.5=3.5 +log(\frac{conjugate base}{weak acid} )\\-2.0=log(\frac{conjugate base}{weak acid} )\\10^{-2.0} =\frac{conjugate base}{weak acid}\\\frac{conjugate base}{weak acid}=0.01=\frac{1}{100}$

When aspirin is absorbed more readily the ratio of conjugate base to acid is 1 to 100, being the acid the predominant form.

6 0

4 years ago

The goose has a mass of 19.2 lb (pounds) and is flying at 7.10 miles/h (miles per hour). What is the kinetic energy of the goose

nata0808 [166]

Answer:

43.868 J

Explanation:

Kinetic energy of a body is the amount of energy possessed by a moving body. The SI unit of kinetic energy is the joule (kg⋅m²⋅s⁻²).

According to classical mechanics, kinetic energy = 1/2 m·v²

Where, m= mass in kg and v= velocity in m/s

Given: m = 19.2 lb and v = 7.10 miles/h

Since, 1 lb= 0.453592 kg

∴ m = 19.2 lb = 19.2 × 0.453592 kg = 8.709 kg

Also, 1 mi = 1609.34 m and 1 h = 3600 sec

∴ v = 7.10 mi/h = 7.10 × 1609.34 m ÷ 3600 sec = 3.174 m/sec

Therefore, kinetic energy of the goose = 1/2 m·v² = 1/2 × (8.709 kg)× (3.174 m/sec)² = 43.868 J

5 0

3 years ago